PATENT APPLICATION GLYCEROL LINKED PEGYLATED SUGARS AND GLYCOPEPTIDES CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present application claims priority to U.S. Provisional Patent Application No. 60/828,208, filed on October 4,2006, which is incorporated herein by reference in its entirety for all purposes. SUMMARY OF THE INVENTION [0002] In an exemplary embodiment, "glycopegylated" molecules of the invention are produced by the enzyme mediated formation of a conjugate between a glycosylated or non-glycosylated peptide and an enzymatically transferable saccharyl moiety that includes a modifying group, such as a polymeric modifying group such as poly(ethylene glycol), within its structure. In an exemplary embodiment, the peptide is a member selected from bone morphogenetic proteins (e.g., BMP-1, BMP-2, BMP-3, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, BMP-14, BMP-15), neurotrophins (e.g., NT-3, NT-4, NT-5), growth differentiation factors (e.g., GDF-5), glial cell line-derived neurotrophic factor (GDNF), brain derived neurotrophic factor (BDNF), nerve growth factor (NGF), von Willebrand factor (vWF) protease, Factor VII, Factor VIIa, Factor VIII, Factor IX, Factor X, Factor XI, B-domain deleted Factor VIII, vWF-Factor VIII fusion protein having full-length Factor VIII, vWF-Factor VIII fusion protein having B-domain deleted Factor VIII, erythropoietin (EPO), granulocyte colony stimulating factor (G-CSF), Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF)interferon alpha, interferon beta, interferon gamma, ai-antitrypsin (ATT, or -Schiff base formation-M-eduction), or the glycosyl linking group may be intact. An "intact glycosyl linking group" refers to a linking group that is derived from a glycosyl moiety in which the saccharide monomer that links the modifying group and to the remainder of the conjugate is not degraded, e.g., oxidized, e.g., by sodium metaperiodate. "Intact glycosyl linking groups" of the invention may be derived from a naturally occurring oligosaccharide by addition of glycosyl unit(s) or removal of one or more glycosyl unit from a parent saccharide structure. [0063] The term, "non-glycosidic modifying group", as used herein, refers to modifying groups which do not include a naturally occurring sugar linked directly to the glycosyl linking group. [0064] The term "targeting moiety," as used herein, refers to species that will selectively localize in a particular tissue or region of the body. The localization is mediated by specific recognition of molecular determinants, molecular size of the targeting agent or conjugate, ionic interactions, hydrophobic interactions and the like. Other mechanisms of targeting an agent to a particular tissue or region are known to those of skill in the art. Exemplary targeting moieties include antibodies, antibody fragments, transferrin, HS-glycoprotein, coagulation factors, serum proteins, P-glycoprotein, G-CSF, GM-CSF, M-CSF, EPO and the like. [0065] As used herein, "therapeutic moiety" means any agent useful for therapy including, but not limited to, antibiotics, anti-inflammatory agents, anti-tumor drugs, cytotoxins, and radioactive agents. "Therapeutic moiety" includes prodrugs of bioactive agents, constructs in which more than one therapeutic moiety is bound to a carrier, e.g, multivalent agents. Therapeutic moiety also includes proteins and constructs that include proteins. Exemplary proteins include, but are not limited to, Granulocyte Colony Stimulating Factor (GCSF), Granulocyte Macrophage Colony Stimulating Factor (GMCSF), Interferon (e.g., Interferon-a, -p, -y), Interleukin (e.g., Interleukin II), serum proteins (e.g., Factors VII, VIIa, VIII, IX, and X), Human Chorionic Gonadotropin (HCG), Follicle Stimulating Hormone (FSH) and Lutenizing Hormone (LH) and antibody fusion proteins (e.g. Tumor Necrosis Factor Receptor ((TNFR)/Fc domain fusion protein)). [0066] As used herein, "pharmaceutically acceptable carrier" includes any material, which when combined with the conjugate retains the conjugates' activity and is non-reactive with the subject's immune systems. Examples include, but are not limited to, any of the standard pharmaceutical carriers such as a phosphate buffered saline solution, water, emulsions such as oil/water emulsion, and various types of wetting agents. Other carriers may also include sterile solutions, tablets including coated tablets and capsules. Typically such carriers contain excipients such as starch, milk, sugar, certain types of clay, gelatin, stearic acid or salts thereof, magnesium or calcium stearate, talc, vegetable fats or oils, gums, glycols, or other known excipients. Such carriers may also include flavor and color additives or other ingredients. Compositions comprising such carriers are formulated by well known conventional methods. [0067] As used herein, "administering," means oral administration, administration as a suppository, topical contact, intravenous, intraperitoneal, intramuscular, intralesional, intranasal or subcutaneous administration, or the implantation of a slow-release device e.g., a mini-osmotic pump, to the subject. Administration is by any route including parenteral, and transmucosal (e.g., oral, nasal, vaginal, rectal, or transdermal). Parenteral administration includes, e.g., intravenous, intramuscular, intra-arteriole, intradermal, subcutaneous, intraperitoneal, intraventricular, and intracranial. Moreover, where injection is to treat a tumor, e.g., induce apoptosis, administration may be directly to the tumor and/or into tissues surrounding the tumor. Other modes of delivery include, but are not limited to, the use of liposomal formulations, intravenous infusion, transdermal patches, etc. [0068] The term "ameliorating" or "ameliorate" refers to any indicia of success in the treatment of a pathology or condition, including any objective or subjective parameter such as abatement, remission or diminishing of symptoms or an improvement in a patient's physical or mental well-being. Amelioration of symptoms can be based on objective or subjective parameters; including the results of a physical examination and/or a psychiatric evaluation. [0069] The term "therapy" refers to "treating" or "treatment" of a disease or condition including preventing the disease or condition from occurring in an animal that may be predisposed to the disease but does not yet experience or exhibit symptoms of the disease (prophylactic treatment), inhibiting the disease (slowing or arresting its development), providing relief from the symptoms or side-effects of the disease (including palliative treatment), and relieving the disease (causing regression of the disease). [0070] The term "effective amount" or "an amount effective to" or a "therapeutically effective amount" or any grammatically equivalent term means the amount that, when administered to an animal for treating a disease, is sufficient to effect treatment for that disease. [0071] The term "isolated" refers to a material that is substantially or essentially free from components, which are used to produce the material. For peptide conjugates of the invention, the term "isolated" refers to material that is substantially or essentially free from components which normally accompany the material in the mixture used to prepare the peptide conjugate. "Isolated" and "pure" are used interchangeably. Typically, isolated peptide conjugates of the invention have a level of purity preferably expressed as a range. The lower end of the range of purity for the peptide conjugates is about 60%, about 70% or about 80% and the upper end of the range of purity is about 70%, about 80%, about 90% or more than about 90%. [0072] When the peptide conjugates are more than about 90% pure, their purities are also preferably expressed as a range. The lower end of the range of purity is about 90%, about 92%, about 94%, about 96% or about 98%. The upper end of the range of purity is about 92%, about 94%, about 96%, about 98% or about 100% purity. [0073] Purity is determined by any art-recognized method of analysis (e.g., band intensity on a silver stained gel, polyacrylamide gel electrophoresis, HPLC, or a similar means). [0074] "Essentially each member of the population," as used herein, describes a characteristic of a population of peptide conjugates of the invention in which a selected percentage of the modified sugars added to a peptide are added to multiple, identical acceptor sites on the peptide. "Essentially each member of the population" speaks to the "homogeneity" of the sites on the peptide conjugated to a modified sugar and refers to conjugates of the invention, which are at least about 80%, preferably at least about 90% and more preferably at least about 95% homogenous. [0075] "Homogeneity," refers to the structural consistency across a population of acceptor moieties to which the modified sugars are conjugated. Thus, in a peptide conjugate of the invention in which each modified sugar moiety is conjugated to an acceptor site having the same structure as the acceptor site to which every other modified sugar is conjugated, the peptide conjugate is said to be about 100% homogeneous. Homogeneity is typically expressed as a range. The lower end of the range of homogeneity for the peptide conjugates is about 60%, about 70% or about 80% and the upper end of the range of purity is about 70%, about 80%, about 90% or more than about 90%. [0076] When the peptide conjugates are more than or equal to about 90% homogeneous, their homogeneity is also preferably expressed as a range. The lower end of the range of homogeneity is about 90%, about 92%, about 94%, about 96% or about 98%. The upper end of the range of purity is about 92%, about 94%, about 96%, about 98% or about 100% homogeneity. The purity of the peptide conjugates is typically determined by one or more methods known to those of skill in the art, e.g., liquid chromatography-mass spectrometry (LC-MS), matrix assisted laser desorption mass time of flight spectrometry (MALDITOF), capillary electrophoresis, and the like. [0077] "Substantially uniform glycoform" or a "substantially uniform glycosylation pattern," when referring to a glycopeptide species, refers to the percentage of acceptor moieties that are glycosylated by the glycosyltransferase of interest {e.g., fucosyltransferase). For example, in the case of a a 1,2 fucosyltransferase, a substantially uniform fucosylation pattern exists if substantially all (as defined below) of the Galß1,4-GlcNAc-R and sialylated analogues thereof are fucosylated in a peptide conjugate of the invention. In the fucosylated structures set forth herein, the Fuc-GlcNAc linkage is generally a 1,6 or a 1,3, with a 1,6 generally preferred. It will be understood by one of skill in the art, that the starting material may contain glycosylated acceptor moieties (e.g., fucosylated Galß1,4-GlcNAc-R moieties). Thus, the calculated percent glycosylation will include acceptor moieties that are glycosylated by the methods of the invention, as well as those acceptor moieties already glycosylated in the starting material. [0078] The term "substantially" in the above definitions of "substantially uniform" generally means at least about 40%, at least about 70%, at least about 80%, or more preferably at least about 90%, and still more preferably at least about 95% of the acceptor moieties for a particular glycosyltransferase are glycosylated. [0079] Where substituent groups are specified by their conventional chemical formulae, written from left to right, they equally encompass the chemically identical substituents, which would result from writing the structure from right to left, e.g., -CH2O- is intended to also recite -OCH2-. [0080] The term "alkyl," by itself or as part of another substituent means, unless otherwise stated, a straight or branched chain, or cyclic hydrocarbon radical, or combination thereof, which may be fully saturated, mono- or polyunsaturated and can include di- and multivalent radicals, having the number of carbon atoms designated (i.e. C1-C10 means one to ten carbons). Examples of saturated hydrocarbon radicals include, but are not limited to, groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, sec-butyl, cyclohexyl, (cyclohexyl)methyl, cyclopropylmethyl, homologs and isomers of, for example, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like. An unsaturated alkyl group is one having one or more double bonds or triple bonds. Examples of unsaturated alkyl groups include, but are not limited to, vinyl, 2-propenyl, crotyl, 2-isopentenyl, 2-(butadienyl), 2,4-pentadienyl, 3-(1,4-pentadienyl), ethynyl, 1- and 3-propynyl, 3-butynyl, and the higher homologs and isomers. The term "alkyl," unless otherwise noted, is also meant to include those derivatives of alkyl defined in more detail below, such as "heteroalkyl." Alkyl groups that are limited to hydrocarbon groups are termed "homoalkyl". [0081] The term "alkylene" by itself or as part of another substituent means a divalent radical derived from an alkane, as exemplified, but not limited, by -CH2CH2CH2CH2-, and further includes those groups described below as "heteroalkylene." Typically, an alkyl (or alkylene) group will have from 1 to 24 carbon atoms, with those groups having 10 or fewer carbon atoms being preferred in the present invention. A "lower alkyl" or "lower alkylene" is a shorter chain alkyl or alkylene group, generally having eight or. fewer carbon atoms. [0082] The terms "alkoxy," "alkylamino" and "alkylthio" (or thioalkoxy) are used in their conventional sense, and refer to those alkyl groups attached to the remainder of the molecule via an oxygen atom, an amino group, or a sulfur atom, respectively. [0083] The term "heteroalkyl," by itself or in combination with another term, means, unless otherwise stated, a stable straight or branched chain, or cyclic hydrocarbon radical, or combinations thereof, consisting of the stated number of carbon atoms and at least one heteroatom selected from the group consisting of O, N, Si and S, and wherein the nitrogen and sulfur atoms may optionally be oxidized and the nitrogen heteroatom may optionally be quaternized. The heteroatom(s) O, N and S and Si may be placed at any interior position of the heteroalkyl group or at the position at which the alkyl group is attached to the remainder of the molecule. Examples include, but are not limited to, -CH2-CH2-O-CH3, -CH2-CH2-NH-CH3, -CH2-CH2-N(CH3)-CH3, -CH2-S-CH2-CH3, -CH2-CH2,-S(O)-CH3, -CH2-CH2-S(O)2-CH3, -CH=CH-0o-CH3, -Si(CH3)3, -CH2-CH=N-OCH3, and -CH=CH-N(CH3)-CH3. Up to two heteroatoms may be consecutive, such as, for example, -CH2-NH-OCH3 and -CH2-0-Si(CH3)3. Similarly, the term "heteroalkylene" by itself or as part of another substituent means a divalent radical derived from heteroalkyl, as exemplified, but not limited by, -CH2- CH2-S-CH2-CH2- and -CH2-S-CH2-CH2-NH-CH2-. For heteroalkylene groups, heteroatoms can also occupy either or both of the chain termini (e.g., alkyleneoxy, alkylenedioxy, alkyleneamino, alkylenediamino, and the like). Still further, for alkylene and heteroalkylene linking groups, no orientation of the linking group is implied by the direction in which the formula of the linking group is written. For example, the formula -C(O)2R'- represents both -C(O)2R'-and-R'C(O)2-. [0084] The terms "cycloalkyl" and "heterocycloalkyl", by themselves or in combination with other terms, represent, unless otherwise stated, cyclic versions of "alkyl" and "heteroalkyl", respectively. Additionally, for heterocycloalkyl, a heteroatom can occupy the position at which the heterocycle is attached to the remainder of the molecule. Examples of cycloalkyl include, but are not limited to, cyclopentyl, cyclohexyl, 1-cyclohexenyl, 3-cyclohexenyl, cycloheptyl, and the like. Examples of heterocycloalkyl include, but are not limited to, 1 -(l,2,5,6Ttetrahydropyridyl), 1-piperidinyl, 2-piperidinyl, 3-piperidinyl, 4-morpholinyl, 3-morpholinyl, tetrahydrofuran-2-yl, tetrahydrofuran-3-yl, tetrahydrothien-2-yl, tetrahydrothien-3-yl, 1 -piperazinyl, 2-piperazinyl, and the like. [0085] The terms "halo" or "halogen," by themselves or as part of another substituent, mean, unless otherwise stated, a fluorine, chlorine, bromine, or iodine atom. Additionally, terms such as "haloalkyl," are meant to include monohaloalkyl and polyhaloalkyl. For example, the term "halo(C1-C4)alkyl" is mean to include, but not be limited to, trifluoromethyl, 2,2,2-trifluoroethyl, 4-chlorobutyl, 3-bromopropyl, and the like. [0086] The term "aryl" means, unless otherwise stated, a polyunsaturated, aromatic, substituent that can be a single ring or multiple rings (preferably from 1 to 3 rings), which are fused together or linked covalently. The term "heteroaryl" refers to aryl groups (or rings) that contain from one to four heteroatoms selected from N, O, and S, wherein the nitrogen and sulfur atoms are optionally oxidized, and the nitrogen atom(s) are optionally quaternized. A heteroaryl group can be attached to the remainder of the molecule through a heteroatom. Non-limiting examples of aryl and heteroaryl groups include phenyl, 1-naphthyl, 2-naphthyl, 4-biphenyl, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 3-pyrazolyl, 2-imidazolyl, 4-imidazolyl, pyrazinyl, 2-oxazolyl, 4-oxazolyl, 2-phenyl-4-oxazolyl, 5-oxazolyl, 3-isoxazolyl, 4-isoxazolyl, 5-isoxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 2-furyl, 3-furyl, 2-thienyl, 3-thienyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidyl, 4-pyrimidyl, 5-benzothiazolyl, purinyl, 2-benzimidazolyl, 5-indolyl, 1-isoquinolyl, 5-isoquinolyl, 2-quinoxalinyl, 5-quinoxalinyl, 3- quinolyl, tetrazolyl, benzo[b]furanyl, benzo[b]thienyl, 2,3-dihydrobenzo[l,4]dioxin-6-yl, benzo[l,3]dioxol-5-yl and 6-quinolyl. Substituents for each of the above noted aryl and heteroaryl ring systems are selected from the group of acceptable substituents described below. [0087] For brevity, the term "aryl" when used in combination with other terms (e.g., aryloxy, arylthioxy, arylalkyl) includes both aryl and heteroaryl rings as defined above. Thus, the term "arylalkyl" is meant to include those radicals in which an aryl group is attached to an alkyl group (e.g., benzyl, phenethyl, pyridylmethyl and the like) including those alkyl groups in which a carbon atom (e.g., a methylene group) has been replaced by, for example, an oxygen atom (e.g., phenoxymethyl, 2-pyridyloxymethyl, 3-(l-naphthyloxy)propyl, and the like). [0088] Each of the above terms (e.g., "alkyl," "heteroalkyl," "aryl" and "heteroaryl") is meant to include both substituted and unsubstituted forms of the indicated radical. Preferred substituents for each type of radical are provided below. [0089] Substituents for the alkyl and heteroalkyl radicals (including those groups often referred to as alkylene, alkenyl, heteroalkylene, heteroalkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl) are genetically referred to as "alkyl group substituents," and they can be one or more of a variety of groups selected from, but not limited to: -OR', =0, =NR' =N-OR', -NR'R", -SR', -halogen, -SiR'R"R"', -OC(O)R', -C(O)R', -C02R', -CONR'R", -OC(O)NR'R", -NR"C(O)R\ -NR'-C(O)NR"R'", -NR"C(O)2R', -NR-C(NR'R"R'")=NR"", -NR-C(NR'R")=NR'", -S(O)R', -S(O)2R', -S(O)2NR'R", -NRS02R', -CN and -N02 in a number ranging from zero to (2m'+l), where m' is the total number of carbon atoms in such radical. R', R", R'" and R"" each preferably independently refer to hydrogen, substituted or unsubstituted heteroalkyl, substituted or unsubstituted aryl, e.g., aryl substituted with 1-3 halogens, substituted or unsubstituted alkyl, alkoxy or thioalkoxy groups, or arylalkyl groups. When a compound of the invention includes more than one R group, for example, each of the R groups is independently selected as are each R', R", R'" and R"" groups when more than one of these groups is present. When R' and R" are attached to the same nitrogen atom, they can be combined with the nitrogen atom to form a 5-, 6-, or 7-membered ring. For example, -NR'R" is meant to include, but not be limited to, 1-pyrrolidinyl and 4-morpholinyl. From the above discussion of substituents, one of skill in the art will understand that the term "alkyl" is meant to include groups including carbon atoms bound to groups other than hydrogen groups, such as haloalkyl (e.g., -CF3 and -CH2CF3) and acyl {e.g., -C(O)CH3, -C(O)CF3, -C(O)CH2OCH3, and the like). [0090] Similar to the substituents described for the alkyl radical, substituents for the aryl and heteroaryl groups are generically referred to as "aryl group substituents." The substituents are selected from, for example: halogen, -OR', =0, =NR', =N-OR', -NR'R", -SR', -halogen, -SiR'R"R'", -OC(O)R', -C(O)R', -C02R', -CONR'R", -OC(O)NR'R", -NR"C(O)R', -NR'-C(O)NR"R"', -NR"C(O)2R', -NR-C(NR'R"R"')=NR"", -NR-C(NR'R")=NR'", -S(O)R', -S(O)2R', -S(O)2NR'R", -NRS02R', -CN and -N02, -R', -N3, -CH(Ph)2, fluoro(C1-C4)alkoxy, and fluoro(C1-C4)alkyl, in a number ranging from zero to the total number of open valences on the aromatic ring system; and where R', R", R'" and R"" are preferably independently selected from hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted aryl and substituted or unsubstituted heteroaryl. When a compound of the invention includes more than one R group, for example, each of the R groups is independently selected as are each R', R", R'" and R"" groups when more than one of these groups is present. In the schemes that follow, the symbol X represents "R" as described above. [0091] Two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula -T-C(O)-(CRR')u-U-, wherein T and U are independently -NR-, -0-, -CRR'- or a single bond, and u is an integer of from 0 to 3. Alternatively, two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula -A-(CH2)r-B-, wherein A and B are independently -CRR'-, -0-, -NR-, -S-, -S(O)-, -S(O)2-, -S(O)2NR'- or a single bond, and r is an integer of from 1 to 4. One of the single bonds of the new ring so formed may optionally be replaced with a double bond. Alternatively, two of the substituents on adjacent atoms of the aryl or heteroaryl ring may optionally be replaced with a substituent of the formula -(CRR')z-X-(CR"R'")d-, where z and d are independently integers of from 0 to 3, and X is -0-, -NR'-, -S-, -S(O)-, -S(O)2-, or -S(O)2NR'-. The substituents R, R',R" and R"' are preferably independently selected from hydrogen or substituted or unsubstituted (C1-C6)alkyl. [0092] As used herein, the term "heteroatom" is meant to include oxygen (O), nitrogen (N), sulfur (S) and silicon (Si). [0093] As used herein, Factor VII peptide refers to both Factor VII and Factor VIIa peptides. The terms generally refer to variants and mutants of these peptides, including addition, deletion, substitution and fusion protein mutants. Where both Factor VII and Factor VIIa are used, the use is intended to be illustrative of two species of the genus "Factor VII peptide". [0094] The invention is meant to include salts of the compounds of the invention which are prepared with relatively nontoxic acids or bases, depending on the particular substituents found on the compounds described herein. When compounds of the present invention contain relatively acidic functionalities, base addition salts can be obtained by contacting the neutral form of such compounds with a sufficient amount of the desired base, either neat or in a suitable inert solvent. Examples of base addition salts include sodium, potassium, lithium, calcium, ammonium, organic amino, or magnesium salt, or a similar salt. When compounds of the present invention contain relatively basic functionalities, acid addition salts can be obtained by contacting the neutral form of such compounds with a sufficient amount of the desired acid, either neat or in a suitable inert solvent. Examples of acid addition salts include those derived from inorganic acids like hydrochloric, hydrobromic, nitric, carbonic, monohydrogencarbonic, phosphoric, monohydrogenphosphoric, dihydrogenphosphoric, sulfuric, monohydrogensulfuric, hydriodic, or phosphorous acids and the like, as well as the salts derived from relatively nontoxic organic acids like acetic, propionic, isobutyric, maleic, malonic, benzoic, succinic, suberic, fumaric, lactic, mandelic, phthalic, benzenesulfonic, p-tolylsulfonic, citric, tartaric, methanesulfonic, and the like. Also included are salts of amino acids such as arginate and the like, and salts of organic acids like glucuronic or galactunoric acids and the like (see, for example, Berge et al., "Pharmaceutical Salts", Journal of Pharmaceutical Science 66: 1-19 (1977)). Certain specific compounds of the present invention contain both basic and acidic functionalities that allow the compounds to be converted into either base or acid addition salts. [0095] The neutral forms of the compounds are preferably regenerated by contacting the salt with a base or acid and isolating the parent compounds in the conventional manner. The parent form of the compound differs from the various salt forms in certain physical properties, such as solubility in polar solvents. [0096] "Salt counterion", as used herein, refers to positively charged ions that associate with a compound of the invention when one of its moieties is negatively charged (e.g. COO-). Examples of salt counterions include H+, H3O+, ammonium, potassium, calcium, lithium, magnesium and sodium. [0097] As used herein, the term "CMP-SA-PEG" is a cytidine monophosphate molecule which is conjugated to a sialic acid which comprises a polyethylene glycol moiety. If a length of the polyethylene glycol chain is not specified, then any PEG chain length is possible (e.g. lkD, 2 kD, 5 kD, 10 kD, 20 kD, 30 kD, 40 kD). An exemplary CMP-SA-PEG is compound 5 in Scheme 1. /. Introduction [0098] To improve the effectiveness of recombinant peptides used for therapeutic purposes, the present invention provides conjugates of glycosylated and unglycosylated peptides with a modifying group. The modifying groups can be selected from polymeric modifying groups such as, e.g., PEG (m-PEG), PPG (m-PPG), etc., therapeutic moieties, diagnostic moieties, targeting moieties and the like. Modification of the peptides, e.g., with a water-soluble polymeric modifying group can improve the stability and retention time of the recombinant peptides in a patient's circulation, and/or reduce the antigenicity of recombinant peptides. [0099] The peptide conjugates of the invention can be formed by the enzymatic attachment of a modified sugar to the glycosylated or unglycosylated peptide. A glycosylation site and/or a modified glycosyl group provides a locus for conjugating a modified sugar bearing a modifying group to the peptide, e.g., by glycoconjugation. [0100] The methods of the invention also make it possible to assemble peptide conjugates and glycopeptide conjugates that have a substantially homogeneous derivatization pattern. The enzymes used in the invention are generally selective for a particular amino acid residue, combination of amino acid residues, particular glycosyl residues, or combination of glycosyl residues of the peptide. The methods are also practical for large-scale production of peptide conjugates. Thus, the methods of the invention provide a practical means for large-scale preparation of peptide conjugates having preselected uniform derivatization patterns. The methods are particularly well suited for modification of therapeutic peptides, including but not limited to, glycopeptides that are incompletely glycosylated during production in cell culture cells {e.g., mammalian cells, insect cells, plant cells, fungal cells, yeast cells, or prokaryotic cells) or transgenic plants or animals. [0101] The present invention also provides conjugates of glycosylated and unglycosylated peptides with increased therapeutic half-life due to, for example, reduced clearance rate, or reduced rate of uptake by the immune or reticuloendothelial system (RES). Moreover, the methods of the invention provide a means for masking antigenic determinants on peptides, thus reducing or eliminating a host immune response against the peptide. Selective attachment of targeting agents can also be used to target a peptide to a particular tissue or cell surface receptor that is specific for the particular targeting agent. [0102] Determining optimal conditions for the preparation of peptide conjugates with water-soluble polymers, e.g., involves the optimization of numerous parameters, which are dependent on the identity of the peptide and of the water-soluble polymer. For example, when the polymer is poly(ethylene glycol), e.g., a branched poly(ethylene glycol), a balance is preferably established between the amount of polymer utilized in the reaction and the viscosity of the reaction mixture attributable to the presence of the polymer: if the polymer is too highly concentrated, the reaction mixture becomes viscous, slowing the rate of mass transfer and reaction. [0103] Furthermore, though it is intuitively apparent to add an excess of enzyme, the present inventors have recognized that, when the enzyme is present in too great of an excess, the excess enzyme becomes a contaminant whose removal requires extra purification steps and material and unnecessarily increases the cost of the final product. [0104] Moreover, it is generally desired to produce a peptide with a controlled level of modification. In some instances, it is desireable to add one modified sugar preferentially. In other instances, it is desireable to add two modified sugars preferentially. Thus, the reaction conditions are preferably controlled to influence the degree of conjugation of the modifying groups to the peptide. [0105] The present invention provides conditions under which the yield of a peptide, having the desired level of conjugation, is maximized. The conditions in the exemplary embodiments of the inventions also recognize the expense of the various reagents and the materials and time necessary to purify the product: the reaction conditions set forth herein are optimized to provide excellent yields of the desired product, while minimizing waste of costly reagents. //. The Compositions of Matter/Peptide Conjugates [0106] In a first aspect, the present invention provides a conjugate between a modified sugar and a peptide. The present invention also provides a conjugate between a modifying group and a peptide. A peptide conjugate can have one of several forms. In an exemplary embodiment, a peptide conjugate can comprise a peptide and a modifying group linked to an amino acid of the peptide through a glycosyl linking group. In another exemplary embodiment, a peptide conjugate can comprise a peptide and a modifying group linked to a glycosyl reside of the peptide through a glycosyl linking group. In another exemplary embodiment, the peptide conjugate can comprise a peptide and a glycosyl linking group which is bound to both a glycopeptide carbohydrate and directly to an amino acid residue of the peptide backbone. In yet another exemplary embodiment, a peptide conjugate can comprise a peptide and a modifying group linked directly to an amino acid residue of the peptide. In this embodiment, the peptide conjugate may not comprise a glycosyl group. In any of these embodiments, the peptide may or not be glycosylated. [0107] The conjugates of the invention will typically correspond to the general structure: (STRUCTURE REMOVED) in which the symbols a, b, c, d and s represent a positive, non-zero integer; and t is either 0 or a positive integer. The "agent", or modifying group, can be a therapeutic agent, a bioactive agent, a detectable label, a polymeric modifying group such as a water-soluble polymer (e.g., PEG, m-PEG, PPG, and m-PPG) or the like. The "agent", or modifying group, can be a peptide, e.g., enzyme, antibody, antigen, etc. The linker can be any of a wide array of linking groups, infra. Alternatively, the linker may be a single bond or a "zero order linker." //. A. Peptide [0108] The peptide in the peptide conjugate is a member selected from the peptides in FIG. 7. In these cases, the peptide in the peptide conjugate is a member selected from bone morphogenetic proteins (e.g., BMP-1, BMP-2, BMP-3, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, BMP-14, BMP-15), neurotrophins (e.g., NT-3, NT-4, NT-5), growth differentiation factors (e.g., GDF-5), glial cell line-derived neurotrophic factor (GDNF), brain derived neurotrophic factor (BDNF), nerve growth factor (NGF), von Willebrand factor (vWF) protease, Factor VII, Factor VIIa, Factor VIII, Factor IX, Factor X, Factor XI, B-domain deleted Factor VIII, vWF-Factor VIII fusion protein having full-length Factor VIII, vWF-Factor VIII fusion protein having B-domain deleted Factor VIII, erythropoietin (EPO), granulocyte colony stimulating factor (G-CSF), Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF), interferon alpha, interferon beta, interferon gamma, cti-antitrypsin (ATT, or a-1 protease inhibitor, glucocerebrosidase, Tissue-Type Plasminogen Activator (TPA), Interleukin-2 (IL-2), urokinase, human DNase, insulin, Hepatitis B surface protein (HbsAg), human growth hormone, TNF Receptor-IgG Fc region fusion protein (Enbrel™), anti-HER2 monoclonal antibody (Herceptin™), monoclonal antibody to Protein F of Respiratory Syncytial Virus (Synagis™), monoclonal antibody to TNF-a (Remicade™), monoclonal antibody to glycoprotein IIb/IIIa (Reopro™), monoclonal antibody to CD20 (Rituxan™), anti-thrombin III (AT III), human Chorionic Gonadotropin (hCG), alpha-galactosidase (Fabrazyme™), alpha-iduronidase (Aldurazyme™), follicle stimulating hormone, beta-glucosidase, anti-TNF-alpha monoclonal antibody, glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), beta-glucosidase, alpha-galactosidase A and fibroblast growth factor. In certain embodiments, the peptide in the peptide conjugate is Factor VIII. In other embodiments, the peptide in the peptide conjugate is interferon alpha. [0109] In an exemplary embodiment, the polymeric modifying group has a structure including a moiety according to the following formulae: (FORMULA REMOVED) [0110] In an exemplary embodiment, m and n are integers independently selected from about 1 to about 5000, preferably from about 100 to about 4000, more preferably from about 200 to about 3000, even more preferably from about 300 to about 2000 and still more preferably from about 400 to about 1000 . In an exemplary embodiment, m and n are integers independently selected from about 1 to about 500. In an exemplary embodiment, m and n are integers independently selected from about 1 to about 70, about 70 to about 150, about 150 to about 250, about 250 to about 375 and about 375 to about 500. In an exemplary embodiment, m and n are integers independently selected from about 10 to about 35, about 45 to about 65, about 95 to about 130, about 210 to about 240, about 310 to about 370 and about 420 to about 480. In an exemplary embodiment, m and n are integers selected from about 15 to about 30. In an exemplary embodiment, m and n are integers selected from about 50 to about 65. In an exemplary embodiment, m and n are integers selected from about 100 to about 130. In an exemplary embodiment, m and n are integers selected from about 210 to about 240. In an exemplary embodiment, m and n are integers selected from about 310 to about 370. In an exemplary embodiment, m and n are integers selected from about 430 to about 470. In an exemplary embodiment, A1 and A2 are each members selected from -OH and -OCH3. [0111] Exemplary polymeric modifying groups according to this embodiment include the moiety: (FORMULA REMOVED) [0112] In an exemplary embodiment, in which the modifying group is a branched water-soluble polymer, such as those shown above, it is generally preferred that the concentration of sialidase is about 1.5 to about 2.5 U/L of reaction mixture. More preferably the amount of sialidase is about 2 U/L. [0113] In another exemplary embodiment, about 5 to about 9 grams of peptide substrate is contacted with the amounts of sialidase set forth above. [0114] The modified sugar is present in the reaction mixture in an amount from about 1 gram to about 6 grams, preferably from about 3 grams to about 4 grams. It is generally preferred to maintain the concentration of a modified sugar having a branched water-soluble polymer modifying moiety, e.g., the moiety shown above, at less than about 0.5 mM. [0115] In certain embodiments, the modifying group is a branched poly(alkylene oxide), e.g., poly(ethylene glycol), having a molecular weight from about 20 kD to about 60 kD, more preferably, from about 30 kD to about 50 kD, and even more preferably about 40 kD. In other embodiments, the modifying group is a branched poly(alkylene oxide), e.g., poly(ethylene glycol), having a molecular weight of at least about 80 kD, preferably at least about 100 kD, more preferably at least about 120 kD, at least about 140 kDor at least about 160 kD. In yet another embodiment, the branched poly(alkylene oxide), e.g., poly(ethylene glycol) is at least about 200 kD, such as from at least about 80 kD to at least about 200 kD, including at least about 160 kD and at least about 180 kD. As those of skill will appreciate, the molecular weight of polymers is often polydisperse, thus, the phrase "about" in the context of molecular weight preferably encompasses a range of values around the stated number. For example, a preferred modifying group having a molecular weight of about 40 kD is one that has a molecular weight from about 35 kD to about 45 kD. Those of skill will appreciate that the reliance on branched PEG structures set forth above is simply for clarity of illustration, the PEG can be replaced by substantially any polymeric moiety, including, without limitation those species set forth in the definition of "polymeric moiety" found herein. [0116] Regarding the glycosyltransferase concentration, in a presently preferred embodiment, using the modifying group set forth above, the ratio of glycosyltransferase to peptide is about 40 p,g/mL transferase to about 200 µm peptide. //. B. Modified Sugar [0117] In an exemplary embodiment, the peptides of the invention, such as Factor VIII, interferon alpha, and the peptides listed in FIG. 7, are reacted with a modified sugar, thus forming a peptide conjugate. A modified sugar comprises a "sugar donor moiety" as well as a "sugar transfer moiety". The sugar donor moiety is any portion of the modified sugar that will be attached to the peptide, either through a glycosyl moiety or amino acid moiety, as a conjugate of the invention. The sugar donor moiety includes those atoms that are chemically altered during their conversion from the modified sugar to the glycosyl linking group of the peptide conjugate. The sugar transfer moiety is any portion of the modified sugar that will be not be attached to the peptide as a conjugate of the invention. For example, a modified sugar of the invention is the PEGylated sugar nucleotide, PEG-sialic acid CMP. For PEG-sialic acid CMP, the sugar donor moiety, or PEG-sialyl donor moiety, comprises PEG-sialic acid while the sugar transfer moiety, or sialyl transfer moiety, comprises CMP. [0118] In modified sugars of use in the invention, the saccharyl moiety is preferably a saccharide, a deoxy-saccharide, an amino-saccharide, or an N-acyl saccharide. The term "saccharide" and its equivalents, "saccharyl," "sugar," and "glycosyl" refer to monomers, dimers, oligomers and polymers. The sugar moiety is also functionalized with a modifying group. The modifying group is conjugated to the saccharyl moiety, typically, through conjugation with an amine, sulfhydryl or hydroxyl, e.g., primary hydroxyl, moiety on the sugar. In an exemplary embodiment, the modifying group is attached through an amine moiety on the sugar, e.g., through an amide, a urethane or a urea that is formed through the reaction of the amine with a reactive derivative of the modifying group. [0119] Any saccharyl moiety can be utilized as the sugar donor moiety of the modified sugar. The saccharyl moiety can be a known sugar, such as mannose, galactose or glucose, or a species having the stereochemistry of a known sugar. The general formulae of these modified sugars are: (FORMULA REMOVED) Other saccharyl moieties that are useful in forming the compositions of the invention include, but are not limited to fucose and sialic acid, as well as amino sugars such as glucosamine, galactosamine, mannosamine, the 5-amine analogue of sialic acid and the like. The saccharyl moiety can be a structure found in nature or it can be modified to provide a site for conjugating the modifying group. For example, in one embodiment, the modified sugar provides a sialic acid derivative in which the 9-hydroxy moiety is replaced with an amine. The amine is readily derivatized with an activated analogue of a selected modifying group. [0120] Examples of modified sugars of use in the invention are described in PCT Patent Application No. PCT/US05/002522, which is herein incorporated by reference. [0121] In a further exemplary embodiment, the invention utilizes modified sugars in which the 6-hydroxyl position is converted to the corresponding amine moiety, which bears a linker-modifying group cassette such as those set forth above. Exemplary glycosyl groups that can be used as the core of these modified sugars include Glu, Gal, GalNAc, Glc, GlcNAc, Fuc, Xyl, Man, and the like. A representative modified sugar according to this embodiment has the formula: in which (FORMULA REMOVED) Rn-R14 are members independently selected from H, OH, C(O)CH3, NH, and NH C(O)CH3. R10 is a link to another glycosyl residue (-O-glycosyl) or to an amino acid of the Factor VII/Factor VIIa peptide (-NH-( Factor VII/Factor VIIa)). R14 is OR1, NHR1 or NH-L-R1. R1 and NH-L-R1 are as described above. II. C. Glvcosvl Linking Groups [0122] In an exemplary embodiment, the invention provides a peptide conjugate formed between a modified sugar of the invention and a peptide. In another exemplary embodiment, when the modifying group on the modified sugar includes the moiety: (FORMULA REMOVED) and the peptide in the peptide conjugate is a member selected from the peptides in FIG. 7. In yet another exemplary embodiment, the peptide in the peptide conjugate is a member selected from bone morphogenetic proteins (e.g., BMP-1, BMP-2, BMP-3, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, BMP-14, BMP-15), neurotrophins (e.g., NT-3, NT-4, NT-5), growth differentiation factors (e.g., GDF-5), glial cell line-derived neurotrophic factor (GDNF), brain derived neurotrophic factor (BDNF), nerve growth factor (NGF), von Willebrand factor (vWF) protease, Factor VII, Factor VIIa, Factor VIII, Factor IX, Factor X, Factor XI, B-domain deleted Factor VIII, vWF-Factor VIII fusion protein having full-length Factor VIII, vWF-Factor VIII fusion protein having B-domain deleted Factor VIII, erythropoietin (EPO), granulocyte colony stimulating factor (G-CSF), Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF), interferon alpha, interferon beta, interferon gamma, ai-antitrypsin (ATT, or a-1 protease inhibitor), glucocerebrosidase, Tissue-Type Plasminogen Activator (TPA), Interleukin-2 (IL-2), urokinase, human DNase, insulin, Hepatitis B surface protein (HbsAg), human growth hormone, TNF Receptor-IgG Fc region fusion protein (Enbrel™), anti-HER2 monoclonal antibody (Herceptin™), monoclonal antibody to Protein F of Respiratory Syncytial Virus (Synagis™), monoclonal antibody to TNF-a (Remicade™), monoclonal antibody to glycoprotein IIb/IIIa (Reopro™), monoclonal antibody to CD20 (Rituxan™), anti-thrombin in (AT III), human Chorionic Gonadotropin (hCG), alpha-galactosidase (Fabrazyme™), alpha-iduronidase (Aldurazyme™), follicle stimulating hormone, beta-glucosidase, anti-TNF-alpha monoclonal antibody, glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), beta-glucosidase, alpha-galactosidase A and fibroblast growth factor. In certain embodiments the peptide is Factor VIII or interferon alpha. In this embodiment, the sugar donor moiety (such as the saccharyl moiety and the modifying group) of the modified sugar becomes a "glycosyl linking group". The "glycosyl linking group" can alternatively refer to the glycosyl moiety which is interposed between the peptide and the modifying group. [0123] In an exemplary embodiment, the polymeric modifying group includes a moiety having a structure according to the following formulae: (FORMULA REMOVED) [0124] In an exemplary embodiment, modifying group on the modified sugar includes the moiety: (FORMULA REMOVED) In an exemplary embodiment, A1 and A2 are each members selected from -OH and -OCH3. [0125] Exemplary polymeric modifying groups according to this embodiment include the moiety: (FORMULA REMOVED) [0126] As will be appreciated by those of skill in the art, the PEG moieties in each of the structures shown above can be replaced by any other polymeric moiety, including, without limitation, those species defined herein as "polymeric moieties". [0127] Due to the versatility of the methods available for adding and/or modifying glycosyl residues on a peptide, the glycosyl linking groups can have substantially any structure. In the discussion that follows, the invention is illustrated by reference to the use of selected derivatives of furanose and pyranose. Those of skill in the art will recognize that the focus of the discussion is for clarity of illustration and that the structures and compositions set forth are generally applicable across the genus of glycosyl linking groups and modified sugars. The glycosyl linking group can comprise virtually any mono- or oligo-saccharide. The glycosyl linking groups can be attached to an amino acid either through the side chain or through the peptide backbone. Alternatively the glycosyl linking groups can be attached to the peptide through a saccharyl moiety. This saccharyl moiety can be a portion of an O-linked or N-linked glycan structure on the peptide. [0128] In an exemplary embodiment, the invention provides a peptide conjugate comprising an intact glycosyl linking group having a formula that is selected from: (FORMULA REMOVED) In Formulae I and la R2 is H, CH2OR7, COOR7 or OR7, in which R7 represents H, substituted or unsubstituted alkyl or substituted or unsubstituted heteroalkyl. When COOR7 is a carboxylic acid or carboxylate, both forms are represented by the designation of the single structure COO" or COOH. In Formulae I, la, II or Ha, the symbols R3, R4, R5, R6 and R6' independently represent H, substituted or unsubstituted alkyl, OR8, NHC(O)R9. The index d is 0 or 1. R8 and R9 are independently selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, sialic acid or polysialic acid. At least one of R3, R4, R5, R6 or R6 includes a modifying group. This modifying group can be a polymeric modifying moiety e.g., PEG, linked through a bond or a linking group. In an exemplary embodiment, R6 and R6, together with the carbon to which they are attached are components of the pyruvyl side chain of sialic acid. In a further exemplary embodiment, the pyruvyl side chain is functionalized with the polymeric modifying group. In another exemplary embodiment, R6 and R6, together with the carbon to which they are attached are components of the side chain of sialic acid and the polymeric modifying group is a component of R5. [0129] In an exemplary embodiment, the invention utilizes a glycosyl linking group that has the formula: (FORMULA REMOVED) in which J is a glycosyl moiety, L is a bond or a linker and R1 is a modifying group, e.g., a polymeric modifying group. Exemplary bonds are those that are formed between an NH2 moiety on the glycosyl moiety and a group of complementary reactivity on the modifying group. For example, when R1 includes a carboxylic acid moiety, this moiety may be activated and coupled with the NH2 moiety on the glycosyl residue affording a bond having the structure NHC(O)R'. J is preferably a glycosyl moiety that is "intact", not having been degraded by exposure to conditions that cleave the pyranose or furanose structure, e.g. oxidative conditions, e.g., sodium periodate. [0130] Exemplary linkers include alkyl and heteroalkyl moieties. The linkers include linking groups, for example acyl-based linking groups, e.g., -C(O)NH-, -OC(O)NH-, and the like. The linking groups are bonds formed between components of the species of the invention, e.g., between the glycosyl moiety and the linker (L), or between the linker and the modifying group (R1). Other exemplary linking groups are ethers, thioethers and amines. For example, in one embodiment, the linker is an amino acid residue, such as a glycine residue. The carboxylic acid moiety of the glycine is converted to the corresponding amide by reaction with an amine on the glycosyl residue, and the amine of the glycine is converted to the corresponding amide or urethane by reaction with an activated carboxylic acid or carbonate of the modifying group. [0131] An exemplary species of NH-L-R1 has the formula: -NH{C(O)(CH2)aNH}s{C(O)(CH2)b(OCH2CH2)cO(CH2)dNH}tR1, in which the indices s and t are independently 0 or 1. The indices a, b and d are independently integers from 0 to 20, and c is an integer from 1 to 2500. Other similar linkers are based on species in which an -NH moiety is replaced by another group, for example, -S, -O or -CH2. As those of skill will appreciate one or more of the bracketed moieties corresponding to indices s and t can be replaced with a substituted or unsubstituted alkyl or heteroalkyl moiety. [0132] More particularly, the invention utilizes compounds in which NH-L-R1 is: NHC(O)(CH2)aNHC(O)(CH2)b(OCH2CH2)cO(CH2)dNHR1, NHC(O)(CH2)b(OCH2CH2)cO(CH2)dNHR,,NHC(O)0(CH2)b(OCH2CH2)cO(CH2)dNHR1, NH(CH2)aNHC(O)(CH2)b(OCH2CH2)cO(CH2)dNHR1,NHC(O)(CH2)aNHR1, NH(CH2)aNHR1, and NHR1. In these formulae, the indices a, b and d are independently selected from the integers from 0 to 20, preferably from 1 to 5. The index c is an integer from 1 to about 2500. [0133] In an exemplary embodiment, c is selected such that the PEG moiety is approximately 1 kD, 5 kD, 10, kD, 15 kD, 20 kD, 25 kD, 30 kD, 35 kD, 40 kD or 45 kD. [0134] For the purposes of convenience, the glycosyl linking groups in the remainder of this section will be based on a sialyl moiety. However, one of skill in the art will recognize that another glycosyl moiety, such as mannosyl, galactosyl, glucosyl, or fucosyl, could be used in place of the sialyl moiety. [0135] In an exemplary embodiment, the glycosyl linking group is an intact glycosyl linking group, in which the glycosyl moiety or moieties forming the linking group are not degraded by chemical (e.g., sodium metaperiodate) or enzymatic (e.g., oxidase) processes. Selected conjugates of the invention include a modifying group that is attached to the amine moiety of an amino-saccharide, e.g., mannosamine, glucosamine, galactosamine, sialic acid etc. Exemplary modifying group-intact glycosyl linking group cassettes according to this motif are based on a sialic acid structure, such as those having the formulae: (FORMULA REMOVED) [0136] In the formulae above, R1 and L are as described above. Further detail about the structure of exemplary R1 groups is provided below. [0137] In still a further exemplary embodiment, the conjugate is formed between a peptide and a modified sugar in which the modifying group is attached through a linker at the 6-carbon position of the modified sugar. Thus, illustrative glycosyl linking groups according to this embodiment have the formula: (FORMULA REMOVED) in which the radicals are as discussed above. Glycosyl linking groups include, without limitation, glucose, glucosamine, N-acetyl-glucosamine, galactose, galactosamine, N-acetyl-galactosamine, mannose, mannosamine, N-acetyl-mannosamine, and the like. [0138] In one embodiment, the present invention provides a peptide conjugate comprising the following glycosyl linking group: (FORMULA REMOVED) wherein D is a member selected from -OH and RZ-L-HN-; G is a member selected from H and R1-L- and -C(O)(C1-C6)alkyl; R1 is a moiety comprising a straight-chain or branched poly(ethylene glycol) residue; and L is a linker, e.g., a bond ("zero order"), substituted or unsubstituted alkyl and substituted or unsubstituted heteroalkyl. In exemplary embodiments, when D is OH, G is R1-L-, and when G is -C(O)(C1-C6)aIkyl, D is R'-L-NH-. [0139] In one embodiment, the present invention provides a peptide conjugate comprising the following glycosyl linking group: COOM D is a member selected from -OH and R'-L-HN-;G is a member selected from R'-L- and -C(O)(C1-C6)alkyl-R1; R1 is a moiety comprising a member selected from a straight-chain poly(ethylene glycol) residue and branched poly(ethylene glycol) residue; and M is a member selected from H, a salt counterion and a single negative charge; L is a linker which is a member selected from a bond, substituted or unsubstituted alkyl and substituted or unsubstituted heteroalkyl. In an exemplary embodiment, when D is OH, G is R'-L-. In another exemplary embodiment, when G is -C(O)(C1-C6)alkyl, D is R'-L-NH-. [0140] In any the compounds of the invention, a COOH group can alternatively be COOM, wherein M is a member selected from H, a negative charge, and a salt counterion. [0141] The invention provides a peptide conjugate that includes a glycosyl linking group having the formula: (FORMULA REMOVED) wherein D and G are as described above. [0142] In other embodiments, the glycosyl linking group has the formula: (FORMULA REMOVED) wherein D and G are as described above and the index t is 0 or 1. [0143] In a still further exemplary embodiment, the glycosyl linking group has the formula: (FORMULA REMOVED) wherein D and G are as described above and the index t is 0 or 1. [0144] In yet another embodiment, the glycosyl linking group has the formula: (FORMULA REMOVED) wherein D and G are as described above and the index p represents and integer from 1 to 10; and a is either 0 or 1. [0145] In another exemplary embodiment, the peptide conjugate comprises a glycosyl moiety selected from the formulae: (FORMULA REMOVED) in which the index a and the linker La are as discussed above. The index p is an integer from 1 to 10. The indices t and a are independently selected from 0 or 1. Each of these groups can be included as components of the mono-, bi-, tri- and tetra-antennary saccharide structures set forth above. AA is an amino acid residue of the peptide. One of skill in the art will appreciate that the PEG moiety in these formulae can be replaced with other non-reactive group and polymeric moieties. Exemplary polymers include those of the poly(alkylene oxide) family. Non-reactive groups include groups that are considered to be essentially unreactive, neutral and/ or stable at physiological pH, e.g., H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl and the like. An exemplary polymeric moiety includes the branched structures set forth in Formula IIIa and its exemplars. [0146] In an exemplary embodiment, the PEG moiety has a molecular weight of about 20 kD. In another exemplary embodiment, the PEG moiety has a molecular weight of about 5 kD. In another exemplary embodiment, the PEG moiety has a molecular weight of about 10 kD. In another exemplary embodiment, the PEG moiety has a molecular weight of about 40 kD. In other embodiments, the modifying group is a branched poly(alkylene oxide), e.g., poly(ethylene glycol), having a molecular weight of at least about 80 kD, preferably at least about 100 kD, more preferably at least about 120 kD, at least about 140 kDor at least about 160 kD. In yet another embodiment, the branched poly(alkylene oxide), e.g., poly(ethylene glycol) is at least about 200 kD, such as from at least about 80 kD to at least about 200 kD, including at least about 160 kD and at least about 180 kD. In an exemplary embodiment, the branched polymer is itself attached to a branching moiety (e.g., cysteine, serine, lysine, and oligomers of lysine). [0147] In an exemplary embodiment, the glycosyl linking group is a branched SA-PEG-10 kD moiety based on a cysteine residue, and one or two of these glycosyl linking groups are covalently attached to the peptide. In another exemplary embodiment, the glycosyl linking group is a branched SA-PEG-10 kD moiety based on a lysine residue, and one or two of these glycosyl linking groups are covalently attached to the peptide. In an exemplary embodiment, the glycosyl linking group is a branched SA-PEG-10 kD moiety based on a cysteine residue, and one or two of these glycosyl linking groups are covalently attached to the peptide. In an exemplary embodiment, the glycosyl linking group is a branched SA-PEG-10 kD moiety based on a lysine residue, and one or two of these glycosyl linking groups are covalently attached to the peptide. In an exemplary embodiment, the glycosyl linking group is a branched SA-PEG-5 kD moiety based on a cysteine residue, and one, two or three of these glycosyl linking groups are covalently attached to the peptide. In an exemplary embodiment, the glycosyl linking group is a branched SA-PEG-5 kD moiety based on a lysine residue, and one, two or three of these glycosyl linking groups are covalently attached to the peptide. In an exemplary embodiment, the glycosyl linking group is a branched SA-PEG-40 kD moiety based on a cysteine residue, and one or two of these glycosyl linking groups are covalently attached to the peptide. In an exemplary embodiment, the glycosyl linking group is a branched SA-PEG-40 kD moiety based on a lysine residue, and one or two of these glycosyl linking groups are covalently attached to the peptide. [0148] In another exemplary embodiment, the peptide conjugate comprises a glycosyl moiety selected from the formulae: (FORMULA REMOVED) wherein at least one of R2, R3, R4, R5 or R6 has a structure which is a member selected from (FORMULA REMOVED) in which the variables are as described above. Those of skill will appreciate that the reliance on branched PEG structures set forth above is simply for clarity of illustration, the PEG can be replaced by substantially any polymeric moiety, including, without limitation those species set forth in the definition of "polymeric moiety" found herein. [0149] In an exemplary embodiment, at least one of R2, R3, R4, R5 or R6 has a structure according to the following formula: (FORMULA REMOVED) In an exemplary embodiment, A1 and A2 are each selected from -OH and -OCH3. [0150] Exemplary polymeric modifying groups according to this embodiment include: (FORMULA REMOVED) [0151] In an exemplary embodiment, only one of R2, R3, R4, R5 or R6 has a structure which includes the modifying groups described above. [0152] In another exemplary embodiment, the peptide conjugate comprises a glycosyl moiety selected from the formulae: (FORMULA REMOVED) wherein R2,R3,R4,R5 or R6 are as described above. [0153] In another exemplary embodiment, the peptide conjugate comprises a glycosyl moiety selected from the formulae: (FORMULA REMOVED) (FORMULA REMOVED) [0154] In an exemplary embodiment, l-(R1)W, has a structure according to the following formula: In(FORMULA REMOVED) an exemplary embodiment, A1 and A1 are each selected from -OH and -OCH3. [0155] Exemplary polymeric modifying groups according to this embodiment include: (FORMULA REMOVED) In an exemplary embodiment, m and n are integers independently selected from about 1 to about 1000. In an exemplary embodiment, m and n are integers independently selected from about 1 to about 500. In an exemplary embodiment, m and n are integers independently selected from about 1 to about 70, about 70 to about 150, about 150 to about 250, about 250 to about 375 and about 375 to about 500. In an exemplary embodiment, m and n are integers independently selected from about 10 to about 35, about 45 to about 65, about 95 to about 130, about 210 to about 240, about 310 to about 370 and about 420 to about 480. In an exemplary embodiment, m and n are integers selected from about 15 to about 30. In an exemplary embodiment, m and n are integers selected from about 50 to about 65. In an exemplary embodiment, m and n are integers selected from about 100 to about 130. In an exemplary embodiment, m and n are integers selected from about 210 to about 240. In an exemplary embodiment, m and n are integers selected from about 310 to about 370. In an exemplary embodiment, m and n are integers selected from about 430 to about 470. [0156] In another exemplary embodiment, the peptide conjugate comprises a glycosyl moiety selected from the formulae: (FORMULA REMOVED) wherein the variables are as described above. [0157] In another exemplary embodiment, species according to this embodiment include: (FORMULA REMOVED) wherein the variables are as discussed above. [0158] In an exemplary embodiment, a glycoPEGylated peptide conjugate of the invention is selected from the formulae set forth below: (FORMULA REMOVED) wherein the variables are as described above. [0159] In the formulae above, the index t is an integer from 0 to 1 and the index p is an integer from 1 to 10. The symbol R15 represents H, OH (e.g., Gal-OH), a sialyl moiety, a sialyl linking group (i.e., sialyl linking group-polymeric modifying group (Sia-L-R ), or a sialyl moiety to which is bound a polymer modified sialyl moiety (e.g., Sia-Sia-L-R1) ("Sia-SiaP"')), a galactosyl moiety, a galactosyl linking group (i.e., galactosyl linking group-polymeric modifying group (Gal-L-R1), or a sialyl moiety to which is bound a polymer modified galactosyl moiety (e.g., Sia-Gal-L-R1) ("Sia-GaP')), a galactosaminyl moiety, a galactosaminyl linking group (i.e., galactosaminyl linking group-polymeric modifying group (GalNAc-L-R1), or a sialyl moiety to which is bound a polymer modified galactosaminyl moiety (e.g., Sia-GalNAc-L-R1) ("Sia-GalNAcp"))> a glucosyl moiety, a glucosyl linking group (i.e., glucosyl linking group-polymeric modifying group (Glc-L-R1), or a sialyl moiety to which is bound a polymer modified glucosyl moiety (e.g., Sia-Glc-L-R1) ("Sia-Glcp")), a glucosaminyl moiety, a glucosaminyl linking group (i.e., glucosaminyl linking group-polymeric modifying group (GlcNAc-L-R1), or a sialyl moiety to which is bound a polymer modified glucosaminyl moiety (e.g., Sia-GlcNAc-L-R1) ("Sia-GlcNAc1"')), a mannosyl moiety, a mannosyl linking group (i.e., mannosyl linking group-polymeric modifying group (Man-L-R1), or a sialyl moiety to which is bound a polymer modified mannosyl moiety (e.g., Sia-Man-L-R1) ("Sia-Manp")), a fucosyl moiety, a fucosyl linking group (i.e., fucosyl linking group-polymeric modifying group (Fuc-L-R1), or a sialyl moiety to which is bound a polymer modified fucosyl moiety (e.g., Sia-Fuc-L-R1) ("Sia-FucP"')). Exemplary polymer modified saccharyl moieties have a structure according to Formulae I, la, II or Ha. An exemplary peptide conjugate of the invention will include at least one glycan having a R15 that includes a structure according to Formulae I, la, II and Ha. The oxygen, with the open valence, of Formulae I, la, II or IIa is preferably attached through a glycosidic linkage to a carbon of a Gal or GalNAc moiety. In a further exemplary embodiment, the oxygen is attached to the carbon at position 3 of a galactose residue. In an exemplary embodiment, the modified sialic acid is linked αx2,3-to the galactose residue. In another exemplary embodiment, the sialic acid is linked 80%, preferably greater than 85%, greater than 90%, preferably greater than 95% and more preferably greater than 96%, 97%, 98% or 99%) terminal saccharyl acceptor in a population of sialyl acceptors. In a preferred embodiment, the saccharide has a substantially uniform sialylation pattern (i.e., substantially uniform glycosylation pattern). [0326] Chemical addition of glycosyl moieties is carried out by any art-recognized method. Enzymatic addition of sugar moieties is preferably achieved using a modification of the methods set forth herein, substituting native glycosyl units for the modified sugars used in the invention. Other methods of adding sugar moieties are disclosed in U.S. Patent No. 5,876,980,6,030,815, 5,728,554, and 5,922,577. [0327] Exemplary attachment points for selected glycosyl residue include, but are not limited to: (a) consensus sites for N-linked glycosylation, and sites for O-linked glycosylation; (b) terminal glycosyl moieties that are acceptors for a glycosyltransferase; (c) arginine, asparagine and histidine; (d) free carboxyi groups; (e) free sulfhydryl groups such as those of cysteine; (f) free hydroxyl groups such as those of serine, threonine, or hydroxyproline; (g) aromatic residues such as those of phenylalanine, tyrosine, or tryptophan; or (h) the amide group of glutamine. Exemplary methods of use in the present invention are described in WO 87/05330 published Sep. 11,1987, and in Aplin and Wriston, CRC CRIT. REV. BIOCHEM., pp. 259-306 (1981). [0328] In one embodiment, the invention provides a method for linking two or more peptides through a linking group. The linking group is of any useful structure and may be selected from straight- and branched-chain structures. Preferably, each terminus of the linker, which is attached to a peptide, includes a modified sugar (i.e., a nascent intact glycosyl linking group). [0329] In an exemplary method of the invention, two peptides are linked together via a linker moiety that includes a polymeric (e.g., PEG linker). The construct conforms to the general structure set forth in the cartoon above. As described herein, the construct of the invention includes two intact glycosyl linking groups (i.e., s +1 = 1). The focus on a PEG linker that includes two glycosyl groups is for purposes of clarity and should not be interpreted as limiting the identity of linker arms of use in this embodiment of the invention. [0330] Thus, a PEG moiety is functionalized at a first terminus with a first glycosyl unit and at a second terminus with a second glycosyl unit. The first and second glycosyl units are preferably substrates for different transferases, allowing orthogonal attachment of the first and second peptides to the first and second glycosyl units, respectively. In practice, the (glycosyl)1-PEG-(glycosyl)2 linker is contacted with the first peptide and a first transferase for which the first glycosyl unit is a substrate, thereby forming (peptide) -(glycosyl)1-PEG-(glycosyl)2. Transferase and/or unreacted peptide is then optionally removed from the reaction mixture. The second peptide and a second transferase for which the second glycosyl unit is a substrate are added to the (peptide)1-(glycosyl)1-PEG-(glycosyl)2 conjugate, forming (peptide) -(glycosyl)1-PEG-(glycosyl)2-(peptide)2; at least one of the glycosyl residues is either directly or indirectly O-linked. Those of skill in the art will appreciate that the method outlined above is also applicable to forming conjugates between more than two peptides by, for example, the use of a branched PEG, dendrimer, poly(amino acid), polysaccharide or the like. [0331] In an exemplary embodiment, the peptide that is modified by a method of the invention is a glycopeptide that is produced in mammalian cells (e.g., CHO cells) or in a transgenic animal and thus, contains N- and/or O-linked oligosaccharide chains, which are incompletely sialylated. The oligosaccharide chains of the glycopeptide lacking a sialic acid and containing a terminal galactose residue can be PEGylated, PPGylated or otherwise modified with a modified sialic acid. [0332] In Scheme 1, the amino glycoside 1, is treated with the active ester of a protected amino acid (e.g., glycine) derivative, converting the sugar amine residue into the corresponding protected amino acid amide adduct. The adduct is treated with an aldolase to form a-hydroxy carboxylate 2. Compound 2 is converted to the corresponding CMP derivative by the action of CMP-SA synthetase, followed by catalytic hydrogenation of the CMP derivative to produce compound 3. The amine introduced via formation of the glycine adduct is utilized as a locus of PEG attachment by reacting compound 3 with an activated PEG or PPG derivative (e.g., PEG-C(O)NHS, PEG-OC(O)Orp-mtrophenyl), producing species such as 4 or 5, respectively. (FORMULA REMOVED) CMP-SA-5-NHCOCH2NH—C(OP-PEG 5 In an exemplary embodiment, a modified sugar can be attached to an O-glycan binding site on a peptide. The glycosyltransferases which can be used to produce this peptide conjugate include: for Ser56 (-Glc-(Xyl)n-Gal-SA-PEG - a galactosyltransferase and sialyltransferase; for Ser56 -Glc-(Xyl)n-Xyl-PEG - a xylosyltransferase; and for Ser60-Fuc-GlcNAc-(Gal)n-(SA)m-PEG - a GlcNAc transferase. ///. A. Conjugation of Modified Sugars to Peptides [0333] The PEG modified sugars are conjugated to a glycosylated or non-glycosylated peptide using an appropriate enzyme to mediate the conjugation. Preferably, the concentrations of the modified donor sugar(s), enzyme(s) and acceptor peptide(s) are selected such that glycosylation proceeds until the acceptor is consumed. The considerations discussed below, while set forth in the context of a sialyltransferase, are generally applicable to other glycosyltransferase reactions. A list of preferred sialyltransferases for use in the invention is provided in FIG. 6. [0334] A number of methods of using glycosyltransferases to synthesize desired oligosaccharide structures are known and are generally applicable to the instant invention. Exemplary methods are described, for instance, WO 96/32491, Ito et al., Pure Appl. Chem. 65: 753 (1993), U.S. Pat. Nos. 5,352,670, 5,374,541, 5,545,553, commonly owned U.S. Pat. Nos. 6,399,336, and 6,440,703, and commonly owned published PCT applications, WO 03/031464, WO 04/033651, WO 04/099231, which are incorporated herein by reference. [0335] The present invention is practiced using a single glycosyltransferase or a combination of glycosyltransferases. For example, one can use a combination of a sialyltransferase and a galactosyltransferase. In those embodiments using more than one enzyme, the enzymes and substrates are preferably combined in an initial reaction mixture, or the enzymes and reagents for a second enzymatic reaction are added to the reaction medium once the first enzymatic reaction is complete or nearly complete. By conducting two enzymatic reactions in sequence in a single vessel, overall yields are improved over procedures in which an intermediate species is isolated. Moreover, cleanup and disposal of extra solvents and by-products is reduced. [0336] In a preferred embodiment, each of the first and second enzyme is a glycosyltransferase. In another preferred embodiment, one enzyme is an endoglycosidase. In an additional preferred embodiment, more than two enzymes are used to assemble the modified glycoprotein of the invention. The enzymes are used to alter a saccharide structure on the peptide at any point either before or after the addition of the modified sugar to the peptide. [0337] In another embodiment, the method makes use of one or more exo- or endoglycosidase. The glycosidase is typically a mutant, which is engineered to form glycosyl bonds rather than rupture them. The mutant glycanase typically includes a substitution of an amino acid residue for an active site acidic amino acid residue. For example, when the endoglycanase is endo-H, the substituted active site residues will typically be Asp at position 130, Glu at position 132 or a combination thereof. The amino acids are generally replaced with serine, alanine, asparagine, or glutamine. [0338] The mutant enzyme catalyzes the reaction, usually by a synthesis step that is analogous to the reverse reaction of the endoglycanase hydrolysis step. In these embodiments, the glycosyl donor molecule (e.g., a desired oligo- or mono-saccharide structure) contains a leaving group and the reaction proceeds with the addition of the donor molecule to a GicNAc residue on the protein. For example, the leaving group can be a halogen, such as fluoride. In other embodiments, the leaving group is a Asn, or a Asn-peptide moiety. In further embodiments, the GicNAc residue on the glycosyl donor molecule is modified. For example, the GicNAc residue may comprise a 1,2 oxazoline moiety. [0339] In a preferred embodiment, each of the enzymes utilized to produce a conjugate of the invention are present in a catalytic amount. The catalytic amount of a particular enzyme varies according to the concentration of that enzyme's substrate as well as to reaction conditions such as temperature, time and pH value. Means for determining the catalytic amount for a given enzyme under preselected substrate concentrations and reaction conditions are well known to those of skill in the art. [0340] The temperature at which an above process is carried out can range from just above freezing to the temperature at which the most sensitive enzyme denatures. Preferred temperature ranges are about 0 °C to about 55 °C, and more preferably about 20 ° C to about 37 °C. In another exemplary embodiment, one or more components of the present method are conducted at an elevated temperature using a thermophilic enzyme. [0341] The reaction mixture is maintained for a period of time sufficient for the acceptor to be glycosylated, thereby forming the desired conjugate. Some of the conjugate can often be detected after a few h, with recoverable amounts usually being obtained within 24 h or less. Those of skill in the art understand that the rate of reaction is dependent on a number of variable factors (e.g, enzyme concentration, donor concentration, acceptor concentration, temperature, solvent volume), which are optimized for a selected system. [0342 J The present invention also provides for the industrial-scale production of modified peptides. As used herein, an industrial scale generally produces at least one gram of finished, purified conjugate. [0343] In the discussion that follows, the invention is exemplified by the conjugation of modified sialic acid moieties to a glycosylated peptide. The exemplary modified sialic acid is labeled with PEG. The focus of the following discussion on the use of PEG-modified sialic acid and glycosylated peptides is for clarity of illustration and is not intended to imply that the invention is limited to the conjugation of these two partners. One of skill understands that the discussion is generally applicable to the additions of modified glycosyl moieties other than sialic acid. Moreover, the discussion is equally applicable to the modification of a glycosyl unit with agents other than PEG including other PEG moieties, therapeutic moieties, and biomolecules. [0344] An enzymatic approach can be used for the selective introduction of PEGylated or PPGylated carbohydrates onto a peptide or glycopeptide. The method utilizes modified sugars containing PEG, PPG, or a masked reactive functional group, and is combined with the appropriate glycosyltransferase or glycosynthase. By selecting the glycosyltransferase that will make the desired carbohydrate linkage and utilizing the modified sugar as the donor substrate, the PEG or PPG can be introduced directly onto the peptide backbone, onto existing sugar residues of a glycopeptide or onto sugar residues that have been added to a peptide. [0345] In an exemplary embodiment, an acceptor for a sialyltransferase is present on the peptide to be modified either as a naturally occurring structure or it is placed there recombinantly, enzymatically or chemically. Suitable acceptors, include, for example, galactosyl acceptors such as Galß1,4GlcNAc, Galß,4GalNAc, GaU31,3GalNAc, lacto-N-tetraose, Galßl,3GlcNAc, Galßl,3Ara, Galßl,6GlcNAc, Galpl,4Glc (lactose), and other acceptors known to those of skill in the art (see, e.g., Paulson et al, J. Biol. Chem. 253: 5617-5624 (1978)). Exemplary sialyltransferases are set forth herein. [0346] In one embodiment, an acceptor for the sialyltransferase is present on the glycopeptide to be modified upon in vivo synthesis of the glycopeptide. Such glycopeptides can be sialylated using the claimed methods without prior modification of the glycosylation pattern of the glycopeptide. Alternatively, the methods of the invention can be used to sialylate a peptide that does not include a suitable acceptor; one first modifies the peptide to include an acceptor by methods known to those of skill in the art. In an exemplary embodiment, a GalNAc residue is added by the action of a GalNAc transferase. [0347] In an exemplary embodiment, the galactosyl acceptor is assembled by attaching a galactose residue to an appropriate acceptor linked to the peptide, e.g., a GlcNAc. The method includes incubating the peptide to be modified with a reaction mixture that contains a suitable amount of a galactosyltransferase (e.g., Gah31,3 or Gah31,4), and a suitable galactosyl donor (e.g., UDP-galactose). The reaction is allowed to proceed substantially to completion or, alternatively, the reaction is terminated when a preselected amount of the galactose residue is added. Other methods of assembling a selected saccharide acceptor will be apparent to those of skill in the art. [0348] In yet another embodiment, glycopeptide-linked oligosaccharides are first "trimmed," either in whole or in part, to expose either an acceptor for the sialyltransferase or a moiety to which one or more appropriate residues can be added to obtain a suitable acceptor. Enzymes such as glycosyltransferases and endoglycosidases (see, for example U.S. Patent No. 5,716,812) are useful for the attaching and trimming reactions. In another embodiment of this method, the sialic acid moieties of the peptide are essentially completely removed (e.g., at least 90, at least 95 or at least 99%), exposing an acceptor for a modified sialic acid. [0349] In the discussion that follows, the method of the invention is exemplified by the use of modified sugars having a PEG moiety attached thereto. The focus of the discussion is for clarity of illustration. Those of skill will appreciate that the discussion is equally relevant to those embodiments in which the modified sugar bears a therapeutic moiety, biomolecule or the like. [0350] In an exemplary embodiment of the invention in which a carbohydrate residue is "trimmed" prior to the addition of the modified sugar high mannose is trimmed back to the first generation biantennary structure. A modified sugar bearing a PEG moiety is conjugated to one or more of the sugar residues exposed by the "trimming back." In one example, a PEG moiety is added via a GlcNAc moiety conjugated to the PEG moiety. The modified GlcNAc is attached to one or both of the terminal mannose residues of the biantennary structure. Alternatively, an unmodified GlcNAc can be added to one or both of the termini of the branched species. [0351) In another exemplary embodiment, a PEG moiety is added to one or both of the terminal mannose residues of the biantennary structure via a modified sugar having a galactose residue, which is conjugated to a GlcNAc residue added onto the terminal mannose residues. Alternatively, an unmodified Gal can be added to one or both terminal GlcNAc residues. [0352] In yet a further example, a PEG moiety is added onto a Gal residue using a modified sialic acid such as those discussed above. [0353] In another exemplary embodiment, a high mannose structure is "trimmed back" to the mannose from which the biantennary structure branches. In one example, a PEG moiety is added via a GlcNAc modified with the polymer. Alternatively, an unmodified GlcNAc is added to the mannose, followed by a Gal with an attached PEG moiety. In yet another embodiment, unmodified GlcNAc and Gal residues are sequentially added to the mannose, followed by a sialic acid moiety modified with a PEG moiety. [0354] A high mannose structure can also be trimmed back to the elementary tri-mannosyl core. [0355] In a further exemplary embodiment, high mannose is "trimmed back" to the GlcNAc to which the first mannose is attached. The GlcNAc is conjugated to a Gal residue bearing a PEG moiety. Alternatively, an unmodified Gal is added to the GlcNAc, followed by the addition of a sialic acid modified with a water-soluble sugar. In yet a further example, the terminal GlcNAc is conjugated with Gal and the GlcNAc is subsequently fucosylated with a modified fucose bearing a PEG moiety. [0356] High mannose may also be trimmed back to the first GlcNAc attached to the Asn of the peptide. In one example, the GlcNAc of the GlcNAc-(Fuc)a residue is conjugated wit ha GlcNAc bearing a water soluble polymer. In another example, the GlcNAc of the GlcNAc-(Fuc)a residue is modified with Gal, which bears a water soluble polymer. In a still further embodiment, the GlcNAc is modified with Gal, followed by conjugation to the Gal of a sialic acid modified with a PEG moiety. [0357] Other exemplary embodiments are set forth in commonly owned U.S. Patent application Publications: 20040132640; 20040063911; 20040137557; U.S. Patent application Nos: 10/369,979; 10/410,913; 10/360,770; 10/410,945 and PCT/US02/32263 each of which is incorporated herein by reference. [0358] The Examples set forth above provide an illustration of the power of the methods set forth herein. Using the methods described herein, it is possible to "trim back" and build up a carbohydrate residue of substantially any desired structure. The modified sugar can be added to the termini of the carbohydrate moiety as set forth above, or it can be intermediate between the peptide core and the terminus of the carbohydrate. [0359] In an exemplary embodiment, an existing sialic acid is removed from a glycopeptide using a sialidase, thereby unmasking all or most of the underlying galactosyl residues. Alternatively, a peptide or glycopeptide is labeled with galactose residues, or an oligosaccharide residue that terminates in a galactose unit. Following the exposure of or addition of the galactose residues, an appropriate sialyltransferase is used to add a modified sialic acid. [0360] In another exemplary embodiment, an enzyme that transfers sialic acid onto sialic acid is utilized. This method can be practiced without treating a sialylated glycan with a sialidase to expose glycan residues beneath the sialic acid. An exemplary polymer-modified sialic acid is a sialic acid modified with poly(ethylene glycol). Other exemplary enzymes that add sialic acid and modified sialic acid moieties onto glycans that include a sialic acid residue or exchange an existing sialic acid residue on a glycan for these species include ST3Gal3, CST-II, ST8Sia-II, ST8Sia-III and ST8Sia-IV. [0361] In yet a further approach, a masked reactive functionality is present on the sialic acid. The masked reactive group is preferably unaffected by the conditions used to attach the modified sialic acid to the Factor VII/Factor VIIa peptide. After the covalent attachment of the modified sialic acid to the peptide, the mask is removed and the peptide is conjugated with an agent such as PEG. The agent is conjugated to the peptide in a specific manner by its reaction with the unmasked reactive group on the modified sugar residue. [0362] Any modified sugar can be used with its appropriate glycosyltransferase, depending on the terminal sugars of the oligosaccharide side chains of the glycopeptide. As discussed above, the terminal sugar of the glycopeptide required for introduction of the PEGylated structure can be introduced naturally during expression or it can be produced post expression using the appropriate glycosidase(s), glycosyltransferase(s) or mix of glycosidase(s) and glycosyltransferase(s). [0363] In a further exemplary embodiment, UDP-galactose-PEG is reacted with ß 1,4-galactosyltransferase, thereby transferring the modified galactose to the appropriate terminal N-acetylglucosamine structure. The terminal GlcNAc residues on the glycopeptide may be produced during expression, as may occur in such expression systems as mammalian, insect, plant or fungus, but also can be produced by treating the glycopeptide with a sialidase and/or glycosidase and/or glycosyltransferase, as required. [0364] In another exemplary embodiment, a GlcNAc transferase, such as GNT1-5, is utilized to transfer PEGylated-GlcNAc to a terminal mannose residue on a glycopeptide. In a still further exemplary embodiment, an the N- and/or O-linked glycan structures are enzymatically removed from a glycopeptide to expose an amino acid or a terminal glycosyl residue that is subsequently conjugated with the modified sugar. For example, an endoglycanase is used to remove the N-linked structures of a glycopeptide to expose a terminal GlcNAc as a GlcNAc-linked-Asn on the glycopeptide. UDP-Gal-PEG and the appropriate galactosyltransferase is used to introduce the PEG-galactose functionality onto the exposed GlcNAc. [0365] In an alternative embodiment, the modified sugar is added directly to the peptide backbone using a glycosyltransferase known to transfer sugar residues to the peptide backbone. Exemplary glycosyltransferases useful in practicing the present invention include, but are not limited to, GalNAc transferases (GalNAc Tl-14), GlcNAc transferases, fucosyltransferases, glucosyltransferases, xylosyltransferases, mannosyltransferases and the like. Use of this approach allows the direct addition of modified sugars onto peptides that lack any carbohydrates or, alternatively, onto existing glycopeptides. In both cases, the addition of the modified sugar occurs at specific positions on the peptide backbone as defined by the substrate specificity of the glycosyltransferase and not in a random manner as occurs during modification of a protein's peptide backbone using chemical methods. An array of agents can be introduced into proteins or glycopeptides that lack the glycosyltransferase substrate peptide sequence by engineering the appropriate amino acid sequence into the polypeptide chain. [0366] In each of the exemplary embodiments set forth above, one or more additional chemical or enzymatic modification steps can be utilized following the conjugation of the modified sugar to the peptide. In an exemplary embodiment, an enzyme (e.g., fUcosyltransferase) is used to append a glycosyl unit (e.g., fucose) onto the terminal modified sugar attached to the peptide. In another example, an enzymatic reaction is utilized to "cap" sites to which the modified sugar failed to conjugate. Alternatively, a chemical reaction is utilized to alter the structure of the conjugated modified sugar. For example, the conjugated modified sugar is reacted with agents that stabilize or destabilize its linkage with the peptide component to which the modified sugar is attached. In another example, a component of the modified sugar is deprotected following its conjugation to the peptide. One of skill will appreciate that there is an array of enzymatic and chemical procedures that are useful in the methods of the invention at a stage after the modified sugar is conjugated to the peptide. Further elaboration of the modified sugar-peptide conjugate is within the scope of the invention. [0367] Enzymes and reaction conditions for preparing the conjugates of the present invention are discussed in detail in the parent of the instant application as well as co-owned published PCT patent applications WO 03/031464, WO 04/033651, WO 04/099231. [0368] In a selected embodiment, a peptide, expressed in insect cells, is remodeled such that glycans on the remodeled glycopeptide include a GlcNAc-Gal glycosyl residue. The addition of GlcNAc and Gal can occur as separate reactions or as a single reaction in a single vessel. In this example, GlcNAc-transferase I and Gal-transferase I are used. The modified sialyl moiety is added using ST3Gal-III. [0369] In another embodiment, the addition of GlcNAc, Gal and modified Sia can also occur in a single reaction vessel, using the enzymes set forth above. Each of the enzymatic remodeling and glycoPEGylation steps are carried out individually. [0370] When the peptide is expressed in mammalian cells, different methods are of use. In one embodiment, the peptide is conjugated without need for remodeling prior to conjugation by contacting the peptide with a sialyltransferase that transfers the modified sialic acid directly onto a sialic acid on the peptide forming Sia-Sia-L-R1, or exchanges a sialic acid on the peptide for the modified sialic acid, forming Sia-L-R1. An exemplary enzyme of use in this method is CST-II. Other enzymes that add sialic acid to sialic acid are known to those of skill in the art and examples of such enzymes are set forth the figures appended hereto. [0371] In yet another method of preparing the conjugates of the invention, the peptide expressed in a mammalian system is desialylated using a sialidase. The exposed Gal residue is sialylated with a modified sialic acid using a sialyltransferase specific for O-linked glycans, providing a peptide with an O-linked modified glycan. The desialylated, modified peptide is optionally partially or fully re-sialylated by using a sialyltransferase such as ST3GalIII. [0372] In another aspect, the invention provides a method of making a PEGylated peptide conjugate of the invention. The method includes: (a) contacting a peptide comprising a glycosyl group selected from: (FORMULA REMOVED) with a PEG-sialic acid donor having the formula which is a member selected from (FORMULA REMOVED) wherein the variables are as described above, and an enzyme that transfers PEG-sialic acid from said donor onto a member selected from the GalNAc, Gal and the Sia of said glycosyl group, under conditions appropriate for said transfer. An exemplary modified sialic acid donor is CMP-sialic acid modified, through a linker moiety, with a polymer, e.g., a straight chain or branched poly(ethylene glycol) moiety. As discussed herein, the peptide is optionally glycosylated with GalNAc and/or Gal and/or Sia ("Remodeled") prior to attaching the modified sugar. The remodeling steps can occur in sequence in the same vessel without purification of the glycosylated peptide between steps. Alternatively, following one or more remodeling step, the glycosylated peptide can be purified prior to submitting it to the next glycosylation or glycPEGylation step. In an exemplary embodiment, the method further comprises expressing the peptide in a host. In an exemplary embodiment, the host is a mammalian cell or an insect cell. In another exemplary embodiment, the mammalian cell is a member selected from a BHK cell and a CHO cell and the insect cell is a Spodoptera frugiperda cell. [0373] As illustrated in the examples and discussed further below, placement of an acceptor moiety for the PEG-sugar is accomplished in any desired number of steps. For example, in one embodiment, the addition of GalNAc to the peptide can be followed by a second step in which the PEG-sugar is conjugated to the GalNAc in the same reaction vessel. Alternatively, these two steps can be carried out in a single vessel approximately simultaneously. [0374] In an exemplary embodiment, the PEG-sialic acid donor has the formula: (FORMULA REMOVED) wherein the variables are as described above. [0375] In another exemplary emodiment, the PEG-sialic acid donor has the formula: (FORMULA REMOVED) wherein the variables are as described above. [0376] In a further exemplary embodiment, the peptide is expressed in an appropriate expression system prior to being glycopegylated or remodeled. Exemplary expression systems include Sf-9/baculovirus and Chinese Hamster Ovary (CHO) cells. [0377] In an exemplary embodiment, the invention provides a method of making a peptide conjugate comprising a glycosyl linker comprising a modified sialyl residue having the formula: (FORMULA REMOVED) wherein D is a member selected from -OH and R'-L-HN-; G is a member selected from RJ-L-and -C(OXCi-Ce)alkyl-R1; R1 is a moiety comprising a member selected from a straight-chain poly(ethylene glycol) residue and branched poly(ethylene glycol) residue; M is a member selected from H, a metal and a single negative charge; L is a linker which is a member selected from a bond, substituted or unsubstituted alkyl and substituted or unsubstituted heteroalkyl, such that when D is OH, G is R!-L-, and when G is -C(O)(Cr C6)alkyl,D is R1-L-NH-said method comprising: (a) contacting a peptide comprising the glycosyl moiety: (FORMULA REMOVED) with a PEG-sialic acid donor moiety having the formula: (FORMULA REMOVED) wherein the variables are as described above, and an enzyme that transfers said PEG-sialic acid onto the Gal of said glycosyl moiety, under conditions appropriate for said transfer. [0378] In an exemplary embodiment, L-R1 has the formula: (FORMULA REMOVED) wherein a is an integer selected from 0 to 20. [0379] In another exemplary embodiment, R1 has a structure that is a member selected from: (FORMULA REMOVED) wherein e, f, m and n are integers independently selected from 1 to 2500; and q is an integer selected from 0 to 20. [0380] Large scale or small scale amounts of peptide conjugate can be produced by the methods described herein. In an exemplary embodiment, the amount of peptide is a member selected from about 0.5 mg to about 100kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.1 kg to about 1 kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.5 kg to about 10kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.5 kg to about 3kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.1 kg to about 5kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.08 kg to about 0.2 kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.05 kg to about 0.4kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.1 kg to about 0.7kg. In an exemplary embodiment, the amount of peptide is a member selected from about 0.3 kg to about 1.75 kg. In an exemplary embodiment, the amount of peptide is a member selected from about 25 kg to about 65kg. [0381] The concentration of peptide utilized in the reactions described herein is a member selected from about 0.5 to about 10 mg peptide/mL reaction mixture. In an exemplary embodiment, the peptide concentration is a member selected from about 0.5 to about 1 mg peptide/mL reaction mixture. In an exemplary embodiment, the peptide concentration is a member selected from about 0.8 to about 3 mg peptide/mL reaction mixture. In an exemplary embodiment, the peptide concentration is a member selected from about 2 to about 6 mg peptide/mL reaction mixture. In an exemplary embodiment, the peptide concentration is a member selected from about 4 to about 9 mg peptide/mL reaction mixture. In an exemplary embodiment, the peptide concentration is a member selected from about 1.2 to about 7.8 mg peptide/mL reaction mixture. In an exemplary embodiment, the peptide concentration is a member selected from about 6 to about 9.5 mg peptide/mL reaction mixture. [0382] The concentration of PEGylated nucleotide sugar that can be utilized in the reactions described herein is a member selected from about 0.1 to about 1.0 mM. Factors which may increase or decrease the concentration include the size of the PEG, time of incubation, temperature, buffer components, as well as the type, and concentration, of glycosyltransferase used. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.1 to about 1.0 mM. In an exemplary embodiment, the PEGylated nucleotide concentration is a member selected from about 0.1 to about 0.5 mM. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.1 to about 0.3 mM. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.2 to about 0.7 mM. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.3 to about 0.5 mM. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.4 to about 1.0 mM. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.5 to about 0.7 mM. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.8 to about 0.95 mM. In an exemplary embodiment, the PEGylated nucleotide sugar concentration is a member selected from about 0.55 to about 1.0 mM. [0383] The molar equivalents of the PEGylated nucleotide sugar that can be utilized in the reactions described herein are based on the theoretical number of PEGylated sugars that can be added to the protein. The theoretical number of PEGylated sugars is based on the theoretical number of sugar sites on the protein as well as the MW of the protein when compared to the MW and therefore moles of PEGylated nucleotide sugar. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 1 to 20. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 1 to 20. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 2 to 6. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 3 to 17. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 4 to 11. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 5 to 20. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 1 to 10. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 12 to 20. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 14 to 17. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 7 to 15. In an exemplary embodiment, the molar equivalents of PEGylated nucleotide sugar is an integer selected from 8 to 16. ///. B. Simultaneous Desialvlation and GlvcoPEGvlation [0384] The present invention provides a "one-pot" method of glycopegylating. The one-pot method is distinct from other exemplary processes to make a peptide conjugate, which employ a sequential de-sialylation with sialidase, subsequent purification of the asialopeptide on an anion exchange column, then glycoPEGylation using CMP-sialic acid-PEG and a glycosyltransferase (such as ST3Gal3), exoglycosidase or an endoglycosidase. The peptide conjugate is then purified via anion exchange followed by size exclusion chromatography to produce the purified peptide conjugate. [0385] The one-pot method is an improved method to manufacture a peptide conjugate. In this method, the de-sialylation and glycoPEGylation reactions are combined in a one-pot reaction which obviates the first anion exchange chromatography step used in the previously described process to purify the asialopeptide. This reduction in process steps produces several advantages. First, the number of process steps required to produce the peptide conjugate is reduced, which also reduces the operating complexity of the process. Second, the process time for the production of the peptide conjugates is reduced e.g., from 4 to 2 days. This reduces the raw material requirements and quality control costs associated with in-process controls. Third, the invention utilizes less sialidase, e.g., up to 20-fold less sialidase, e.g., 500 mU/L is required to produce the peptide conjugate relative to the process. This reduction in the use of sialidase significantly reduces the amount of contaminants, such as sialidase, in the reaction mixture. [0386] In an exemplary embodiment, a peptide conjugate is prepared by the following method. In a first step, a peptide is combined with a sialidase, a modified sugar of the invention, and an enzyme capable of catalyzing the transfer of the glycosyl linking group from the modified sugar to the peptide, thus preparing the peptide conjugate. Any sialidase may be used in this method. Exemplary sialidases of use in the invention can be found in the CAZY database (see afmb.cnrs-mrs.fr/CAZY/index.html and www.cazy.org/CAZY). Exemplary sialidases can be purchased from any number of sources (QA-Bio, Calbiochem, Manikin, Prozyme, etc.). In an exemplary embodiment, the sialidase is a member selected from cytoplasmic sialidases, lysosomal sialidases, exo-a sialidases, and endosialidases. In another exemplary embodiment, the sialidase used is produced from bacteria such as Clostridium perfringens or Streptococcus pneumoniae, or from a virus such as an adenovirus. In an exemplary embodiment, the enzyme capable of catalyzing the transfer of the glycosyl linking group from the modified sugar to the peptide is a member selected from a glycosyltransferase, such as sialyltransferases and fucosyltransferases, as well as exoglycosidases and endoglycosidases. In an exemplary embodiment, the enzyme is a glycosyltransferase, which is ST3Gal3. In another exemplary embodiment, the enzyme used is produced from bacteria such as Escherichia Coli or a fungus such as Aspergillus niger. In another exemplary embodiment, the sialidase is added to the peptide before the glycosyltransferase for a specified time, allowing the sialidase reaction to proceed before initiating the GlycoPEGylation reaction with addition of the PEG-sialic acid reagent and the glycosyltransferase. Many of these examples are discussed herein. Finally, any modified sugar described herein can be utilized in this reaction. [0387] In another exemplary embodiment, the method further comprises a 'capping' step. In this step, additional non-PEGylated sialic acid is added to the reaction mixture. In an exemplary embodiment, this sialic acid is added to the peptide or peptide conjugate thus preventing further addition of PEG-sialic acid. In another exemplary embodiment, this sialic acid impedes the function of the glycosyltransferase in the reaction mixture, effectively stopping the addition of glycosyl linking groups to the peptides or peptide conjugates. Most importantly, the sialic acid that is added to the reaction mixture caps the unglycoPEGylated glycans thereby providing a peptide conjugate that has improved pharmaceokinetics. In addition, this sialidase can be added directly the the glycoPEGylation reaction mixture when the extent of PEGylation to certain amounts is desired without prior purification. [0388] In an exemplary embodiment, after the capping step, less than about 50% of the sialylation sites on the peptide or peptide conjugate does not comprise a sialyl moiety. In an exemplary embodiment, after the capping step, less than about 40% of the sialylation sites on the peptide or peptide conjugate does not comprise a sialyl moiety. In an exemplary embodiment, after the capping step, less than about 30% of the sialylation sites on the peptide or peptide conjugate does not comprise a sialyl moiety. In an exemplary embodiment, after the capping step, less than about 20% of the sialylation sites on the peptide OT peptide conjugate does not comprise a sialyl moiety. In an exemplary embodiment, after the capping step, less than about 10% of the sialylation sites on the peptide or peptide conjugate does not comprise a sialyl moiety. In an exemplary embodiment, between about 20% and about 5% of the sialylation sites on the peptide or peptide conjugate does not comprise a sialyl moiety. In an exemplary embodiment, between about 25% and about 10% of the sialylation sites on the peptide or peptide conjugate does not comprise a sialyl moiety. In an exemplary embodiment, after the capping step, essentially all of the sialylation sites on the peptide or peptide conjugate comprise a sialyl moiety. III. C. Desialvlation and Selective Modification of Peptides [0389] In another exemplary embodiment, the present invention provides a method for desialylating a peptide. The method preferably provides a peptide that is at least about 40%, preferably 45%, preferably about 50%, preferably about 55%, preferably about 60%, preferably about 65%, preferably about 70%, preferably about 75%, preferably about 80%, preferably at least 85%, more preferably at least 90%, still more preferably, at least 92%, preferably at least 94%, even more preferably at least 96%, still more preferably at least 98%, and still more preferably 100% disialylated. [0390] The method includes contacting the peptide with a sialidase, preferably for a time period. The preselected time period is sufficient to desialylate the peptide to the degree desired. In a preferred embodiment, the desialylated peptide is separated from the sialidase when the desired degree of desialylation is achieved. An exemplary desialylation reaction and purification cycle is set forth herein. [0391] Those of skill are able to determine an appropriate preselected time period over which to conduct the desialylation reaction. In an exemplary embodiment, the period is less than 24 hours, preferably less than 8 hours, more preferably less than 6 hours, more preferably less than 4 hours, still more preferably less than 2 hours and even more preferably less than 1 hour. [0392] In another exemplary embodiment, in the peptide conjugate preparation at the end of the desialylation reaction, at least 10% of the members of the population of peptides has only a single sialic acid attached thereto, preferably at least 20%, more preferably at least 30%, still more preferably at least 40%, even still more preferably at least 50% and more preferably at least 60%, and still more preferably completely desialylated. [0393] In yet a further exemplary embodiment, in the preparation at the end of the desialylation reaction, at least 10% of the members of the population of peptides is fully desialylated, preferably at least 20%, more preferably at least 30%, even more preferably at least 40%, still more preferably at least 50% and even still more preferably at least 60%. [0394] In still another exemplary embodiment, in the preparation at the end of the desialylation reaction, at least 10%, 20%, 30%, 40%, 50% or 60% of the members of the peptide population has only a single sialic acid, and at least 10%, 20%, 30%, 40%, 50% or 60% of the peptide is fully disialylated. [0395] In a preferred embodiment, in the preparation at the end of the desialylation reaction, at least 50% of the population of peptides is fully disialylated and at least 40% of the members of the peptide population bears only a single sialic acid moiety. [0396] Following desialylation, the peptide is optionally conjugated with a modified sugar. An exemplary modified sugar includes a saccharyl moiety bound to a branched or linear poly(ethylene glycol) moiety. The conjugation is catalyzed by an enzyme that transfers the modified sugar from a modified sugar donor onto an amino acid or glycosyl residue of the peptide. An exemplary modified sugar donor is a CMP-sialic acid that bears a branched or linear poly(ethylene glycol) moiety. An exemplary poly(ethylene glycol) moiety has a molecular weight of at least about 2 kD, more preferably at least about 5 kD, more preferably at least about 10 kD, preferably at least about 20 kD, more preferably at least about 30 kD, and more preferably at least about 40 kD. [0397] In an exemplary embodiment, the enzyme utilized to transfer the modified sugar moiety from the modified sugar donor is a glycosyltransferase, e.g., sialyltransferase. An exemplary sialyltransferase of use in the methods of the invention is ST3Gal3. [0398] An exemplary method of the invention results in a modified peptide bearing at least one, preferably at least two, preferably at least three modifying groups. In one embodiment, the peptide produced bears a single modifying group on the light chain of the peptide. In another embodiment, the method provides a modified peptide that bears a single modifying group on the heavy chain. In still another embodiment, the method provides a modified peptide with a single modifying group on the light chain and a single modifying group on the heavy chain. [0399] In another aspect, the invention provides a method of preparing a modified peptide. The method includes contacting the peptide with a modified sugar donor bearing a modifying group and an enzyme capable of transferring a modified sugar moiety from the modified sugar donor onto an amino acid or glycosyl residue of the peptide. [0400] In an exemplary embodiment, the method provides a population of modified peptides in which at least 40%, preferably at least 50%, preferably at least 60%, more preferably at least 70% and even more preferably at least 80% of the population members are mono-conjugated on the light chain of the peptide. [0401] In an exemplary embodiment, the method provides a population of modified peptides in which at least 40%, preferably at least 50%, preferably at least 60%, more preferably at least 70% and even more preferably at least 80% of the population members are di-conjugated on the light chain of the peptide. [0402] In an exemplary embodiment of this aspect, the method provides a population of modified peptides in which no more than 50%, preferably no more than 30%, preferably no more than 20%, more preferably no more than 10% of the population members are mono-conjugated on the heavy chain of the peptide. [0403] In an exemplary embodiment of this aspect, the method provides a population of modified peptides in which no more than 50%, preferably no more than 30%, preferably no more than 20%, more preferably no more than 10% of the population members are di-conjugated on the heavy chain of the peptide. [0404] The peptide can be subjected to the action of a sialidase prior to the contacting step, or the peptide can be used without prior desialylation. When the peptide is contacted with a sialidase it can be either essentially completely desialylated or only partially desialylated. In a preferred embodiment, the peptide is at least partially desialylated prior to the contacting step. The peptide may be essentially completely desialylated (essentially asialo) or only partially desialylated. In a preferred embodiment, the desialylated peptide is one of the desialylated embodiments described hereinabove. ///. D. Additional aliauots of reagents added in the synthesis of Peptide Conjugates [0405] In an exemplary embodiment of the synthesis of the peptide conjugates described herein, one or more additional aliquots of a reaction component/reagent is added to the reaction mixture after a selected period of time. In an exemplary embodiment, the peptide conjugate is a peptide conjugate. In another exemplary embodiment, the reaction component/reagent added is a modified sugar nucleotide. Introduction of a modified sugar nucleotide into the reaction will increase the likelihood of driving the GlycoPEGylation reaction to completion. In an exemplary embodiment, the nucleotide sugar is a CMP-SA-PEG described herein. In an exemplary embodiment, the reaction component/reagent added is a sialidase. In an exemplary embodiment, the reaction component/reagent added is a glycosyltransferase. In an exemplary embodiment, the reaction component/reagent added is magnesium. In an exemplary embodiment, the additional aliquot added represents about 10%, or 20%, or 30%, or 40%, or 50%, or 60%, or 70%>, or 80% or 90% of the original amount in added at the start of the reaction. In an exemplary embodiment, the reaction component/reagent is added to the reaction about 3 hours, or 6 hours, or 8 hours, or 10 hours, or 12 hours, or 18 hours, or 24 hours, or 30 hours, or 36 hours after its start. ///. E. Purification of Peptide Conjugates [0406] The products produced by the above processes can be used without purification. However, it is usually preferred to recover the product and one or more of the intermediates, e.g., nucleotide sugars, branched and linear PEG species, modified sugars and modified nucleotide sugars. Standard, well-known techniques for recovery of glycosylated peptides such as thin or thick layer chromatography, column chromatography, ion exchange chromatography, or membrane filtration can be used. It is preferred to use membrane filtration, more preferably utilizing a reverse osmotic membrane, or one or more column chromatographic techniques for the recovery as is discussed hereinafter and in the literature cited herein. For instance, membrane filtration wherein the membranes have molecular weight cutoff of about 3000 to about 10,000 can be used to remove proteins such as glycosyl transferases. In certain instances, the molecular weight cutoff differences between the impurity and the product will be utilized in order to ensure product purification. For example, in order to purify product peptide-SA-PEG-40 kD from unreacted CMP-SA-PEG-40 kD, a filter must be chosen that will allow, for example, peptide-SA-PEG-40 kD to remain in the retentate while allowing CMP-SA-PEG-40 kD to flow into the filtrate. Nanofiltration or reverse osmosis can then be used to remove salts and/or purify the product saccharides (see, e.g., WO 98/15581). Nanofilter membranes are a class of reverse osmosis membranes that pass monovalent salts but retain polyvalent salts and uncharged solutes larger than about 100 to about 2,000 Daltons, depending upon the membrane used. Thus, in a typical application, saccharides prepared by the methods of the present invention will be retained in the membrane and contaminating salts will pass through. [0407] If the peptide is produced intracellularly, as a first step, the particulate debris, either host cells or lysed fragments, is removed. Following glycoPEGylation, the PEGylated peptide is purified by art-recognized methods , for example, by centrifugation or ultrafiltration; optionally, the protein may be concentrated with a commercially available protein concentration filter, followed by separating the polypeptide variant from other impurities by one or more steps selected from immunoaffinity chromatography, ion-exchange column fractionation (e.g., on diethylaminoethyl (DEAE) or matrices containing carboxymethyl or sulfopropyl groups), chromatography on Blue-Sepharose, CM Blue-Sepharose, MONO-Q, MONO-S, lentil lectin-Sepharose, WGA-Sepharose, Con A-Sepharose, Ether Toyopearl, Butyl Toyopearl, Phenyl Toyopearl, or protein A Sepharose, SDS-PAGE chromatography, silica chromatography, chromatofocusing, reverse phase HPLC (e.g., silica gel with appended aliphatic groups), gel filtration using, e.g., Sephadex molecular sieve or size-exclusion chromatography, chromatography on columns that selectively bind the polypeptide, and ethanol or ammonium sulfate precipitation. Purification can be used to separate one chain of the Factor VII/Factor VIIa peptide conjugate from the other, as further described later in this section. [0408] Modified glycopeptides produced in culture are usually isolated by initial extraction from cells, enzymes, etc., followed by one or more concentration, salting-out, aqueous ion- exchange, or size-exclusion chromatography steps. Additionally, the modified glycoprotein may be purified by affinity chromatography. Finally, HPLC may be employed for final purification steps. [0409] A protease inhibitor may be included in any of the foregoing steps to inhibit proteolysis and antibiotics or preservatives may be included to prevent the growth of adventitious contaminants. The protease inhibitors used in the foregoing steps may be low molecular weight inhibitors, including antipain, alpha-1-antitrypsin, anti-thrombin, leupeptin, amastatin, chymostatin, banzamidin, as well as other serine protease inhibitors (i.e. serpins). Generally, serine protease inhibitors should be used in concentrations ranging from 0.5 - 100 µm, although chymostatin in cell culture may be used in concentrations upward of 200 µm. Other serine protease inhibitors will include inhibitors specific to the chymotrypsin-like, the subtilisin-like, the alpha/beta hydrolase, or the signal peptidase clans of serine proteases. Besides serine proteases, other types of protease inhibitors may also be used, including cysteine protease inhibitors (1-10 µm) and aspartic protease inhibitors (1-5 µm), as well as non-specific protease inhibitors such as pepstatin (.1-5 µm). Protease inhibitors used in this invention may also include natural protease inhibitors, such as the hirustasin inhibitor isolated from leech. In some embodiments, protease inhibitors will comprise synthetic peptides or antibodies that are able to bind with specificity to the protease catalytic site to stabilize Factor VII/Factor VIIa without interfering with a glycoPEGylation reaction. [0410] Within another embodiment, supernatants from systems which produce the modified glycopeptide of the invention are first concentrated using a commercially available protein concentration filter, for example, an Amicon or Millipore Pellicon ultrafiltration unit. Following the concentration step, the concentrate may be applied to a suitable purification matrix. For example, a suitable affinity matrix may comprise a ligand for the peptide, a lectin or antibody molecule bound to a suitable support. Alternatively, an anion-exchange resin may be employed, for example, a matrix or substrate having pendant DEAE groups. Suitable matrices include acrylamide, agarose, dextran, cellulose, or other types commonly employed in protein purification. Alternatively, a cation-exchange step may be employed. Suitable cation exchangers include various insoluble matrices comprising sulfopropyl or carboxymethyl groups. Sulfopropyl groups are particularly preferred. [0411 ] Other methods of use in purification include size exclusion chromatography (SEC), hydroxyapatite chromatography, hydrophobic interaction chromatography and chromatography on Blue Sepharose. These and other useful methods are illustrated in co-assigned U.S. Provisional Patent No. (Attorney Docket No. 40853-01-5168-Pl, filed May 6, 2005). [0412] One or more RP-HPLC steps employing hydrophobic RP-HPLC media, e.g., silica gel having pendant methyl or other aliphatic groups, may be employed to further purify a polypeptide conjugate composition. Some or all of the foregoing purification steps, in various combinations, can also be employed to provide a homogeneous or essentially homogeneous modified glycoprotein. [0413] The modified glycopeptide of the invention resulting from a large-scale fermentation may be purified by methods analogous to those disclosed by Urdal et ai, J. Chromatog. 296:171 (1984). This reference describes two sequential, RP-HPLC steps for purification of recombinant human IL-2 on a preparative HPLC column. Alternatively, techniques such as affinity chromatography may be utilized to purify the modified glycoprotein. [0414] In an exemplary embodiment, the purification is accomplished by the methods set forth in commonly owned, co-assigned U.S. Provisional Patent No. 60/665,588, filed March 24,2005. [0415] According to the present invention, pegylated peptides or peptide conjugate produced either via sequential de-sialylation or simultaneous sialylation can be purified or resolved by using magnesium chloride gradient. IV. Pharmaceutical Compositions [0416] In another aspect, the invention provides a pharmaceutical composition. The pharmaceutical composition includes a pharmaceutically acceptable diluent and a covalent conjugate between a non-naturally-occurring, PEG moiety, therapeutic moiety or biomolecule and a glycosylated or non-glycosylated peptide. The polymer, therapeutic moiety or biomolecule is conjugated to the peptide via an intact glycosyl linking group interposed between and covalently linked to both the peptide and the polymer, therapeutic moiety or biomolecule. [0417] Pharmaceutical compositions of the invention are suitable for use in a variety of drug delivery systems. Suitable formulations for use in the present invention are found in Remington's Pharmaceutical Sciences, Mace Publishing Company, Philadelphia, PA, 17th ed. (1985). For a brief review of methods for drug delivery, see, Langer, Science 249:1527-1533 (1990). [0418] In an exemplary embodiment, the pharmaceutical formulation comprises a peptide conjugate and a pharmaceutically acceptable diluent which is a member selected from sodium chloride, calcium chloride dihydrate, glycylglycine, polysorbate 80, and mannitol. In another exemplary embodiment, die pharmaceutically acceptable diluent is sodium chloride and glycylglycine. In another exemplary embodiment, the pharmaceutically acceptable diluent is calcium chloride dihydrate and polysorbate 80. In another exemplary embodiment, the pharmaceutically acceptable diluent is mannitol. [0419] The pharmaceutical compositions may be formulated for any appropriate manner of administration, including for example, topical, oral, nasal, intravenous, intracranial, intraperitoneal, subcutaneous or intramuscular administration. For parenteral administration, such as subcutaneous injection, the carrier preferably comprises water, saline, alcohol, a fat, a wax or a buffer. For oral administration, any of the above carriers or a solid carrier, such as mannitol, lactose, starch, magnesium stearate, sodium saccharine, talcum, cellulose, glucose, sucrose, and magnesium carbonate, may be employed. Biodegradable microspheres (e.g., polylactate polyglycolate) may also be employed as carriers for the pharmaceutical compositions of this invention. Suitable biodegradable microspheres are disclosed, for example, in U.S. Patent Nos. 4,897,268 and 5,075,109. [0420] Commonly, the pharmaceutical compositions are administered parenterally, e.g., intravenously. Thus, the invention provides compositions for parenteral administration that include the compound dissolved or suspended in an acceptable carrier, preferably an aqueous carrier, e.g., water, buffered water, saline, PBS and the like. The compositions may contain pharmaceutically acceptable auxiliary substances as required to approximate physiological conditions, such as pH adjusting and buffering agents, tonicity adjusting agents, wetting agents, detergents and the like. [0421] These compositions may be sterilized by conventional sterilization techniques, or may be sterile filtered. The resulting aqueous solutions may be packaged for use as is, or lyophilized, the lyophilized preparation being combined with a sterile aqueous carrier prior to administration. The pH of the preparations typically will be between 3 and 11, more preferably from 5 to 9 and most preferably from 7 and 8. [0422] In some embodiments the glycopeptides of the invention can be incorporated into liposomes formed from standard vesicle-forming lipids. A variety of methods are available for preparing liposomes, as described in, e.g., Szoka et al.,Ann. Rev. Biophys. Bioeng. 9: 467 (1980), U.S. Pat. Nos. 4,235,871,4,501,728 and 4,837,028. The targeting of liposomes using a variety of targeting agents (e.g., the sialyl galactosides of the invention) is well known in the art (see, e.g., U.S. Patent Nos. 4,957,773 and 4,603,044). [0423] Standard methods for coupling targeting agents to liposomes can be used. These methods generally involve incorporation into liposomes of lipid components, such as phosphatidylethanolamine, which can be activated for attachment of targeting agents, or derivatized lipophilic compounds, such as lipid-derivatized glycopeptides of the invention. [0424] Targeting mechanisms generally require that the targeting agents be positioned on the surface of the liposome in such a manner that the target moieties are available for interaction with the target, for example, a cell surface receptor. The carbohydrates of the invention may be attached to a lipid molecule before the liposome is formed using methods known to those of skill in the art (e.g., alkylation or acylation of a hydroxyl group present on the carbohydrate with a long chain alkyl halide or with a fatty acid, respectively). Alternatively, the liposome may be fashioned in such a way that a connector portion is first incorporated into the membrane at the time of forming the membrane. The connector portion must have a lipophilic portion, which is firmly embedded and anchored in the membrane. It must also have a reactive portion, which is chemically available on the aqueous surface of the liposome. The reactive portion is selected so that it will be chemically suitable to form a stable chemical bond with the targeting agent or carbohydrate, which is added later. In some cases it is possible to attach the target agent to the connector molecule directly, but in most instances it is more suitable to use a third molecule to act as a chemical bridge, thus linking the connector molecule which is in the membrane with the target agent or carbohydrate which is extended, three dimensionally, off of the vesicle surface. [0425] The compounds prepared by the methods of the invention may also find use as diagnostic reagents. For example, labeled compounds can be used to locate areas of inflammation or tumor metastasis in a patient suspected of having an inflammation. For this use, the compounds can be labeled with 1251,14C, or tritium. [0426] Preparative methods for species of use in preparing the compositions of the invention are generally set forth in various patent publications, e.g., US 20040137557; WO 04/083258; and WO 04/033651. The following examples are provided to illustrate the conjugates, and methods and of the present invention, but not to limit the claimed invention. EXAMPLES EXAMPLE 1 Desialylation of Factor VIIa. [0427] Factor VIIa which was expressed in serum-free media, Factor VIIa which was produced in serum containing media, plus three Factor VIIa mutants N145Q, N322Q, and analogue DVQ (V158D/E296V/M298Q). [0428] In preparation for enzymatic desialylation, Factor VIIa was dialyzed into MES, 150 mM NaCl, 5 mM CaCl2, 50mM MES, pH 6 overnight at 4°C in Snakeskin dialysis tubing with a MWCO of 10 kD. Desialylation of Factor VIIa (1 mg/mL) was performed with 10 U/L soluble sialidase from Arthrobacter ureafaciens (Calbiochem) at 32°C for 18 hours in the exchanged buffer. EXAMPLE 2 Sialyl-PEGylation of Factor VIIa. [0429] Sialyl-PEGylation ("GlycoPEGylation") was performed on asialo-Factor VIIa (1 mg/mL) with 100 U/L ST3Gal-III and 200 µm CMP-sialic acid-PEG (40 kD, 20 kD, 10 kD, 5 kD, and 2 kD) at 32°C in the desialylation buffer for 2-6 hours. After the proper reaction time had expired, the PEGylated sample was immediately purified to minimize further GlycoPEGylation. [0430] To cap GlycoPEGylated Factor VII/Factor VIIa with samples capped with sialic acid, the sialidase was first removed from the asialo-Factor VIIa by anion-exchange chromatography as indicated below. Excess CMP-sialic acid (5 mM) was added and incubated at 32°C for 2 hours, capping GlycoPEGylated Factor VIIa with sialic acid. The sialyl-PEGylated forms of Factor VIIa were analyzed by non-reducing SDS-PAGE (Tris-glycine gels and/or NuPAGE gels) and a Colloidal Blue Staining Kit, as described by Invitrogen. EXAMPLE 3 Purification ofPEGylated Factor VIIa. [0431] GlycoPEGylated samples of Factor VIIa were purified with a modified anion-exchange method. Samples were handled at 5°C. Immediately before loading the column, 1 g Chelex 100 (BioRad) per 10 mL Factor VIIa solution was added to the remodeled sample. After stirring for 10 min, the suspension was filtered on a cellulose acetate membrane (0.2 urn) with a vacuum system. The retained chelator resin on the filter was washed once with 1-2 mL water per 10 mL bulk. The conductivity of the filtrate was adjusted to 10 mS/cm at 5°C, and adjusted to pH 8.6, if necessary. {0432] Anion exchange was performed at 8-10°C. A column containing Q Sepharose FF was prepared before loading by washing with 1 M NaOH (10 column volumes), water (5 column volumes), 2 M NaCl, 50 mM HOAc, pH 3 (10 column volumes), and equilibrating with 175 mM NaCl, 10 mM glycylglycine, pH 8.6 (10 column volumes). For each PEGylation reaction, 15-20 mg Factor VIIa was loaded on to an XK16 column (Amersham Biosciences) with 10 mL Q Sepharose FF (no more than 2 mg protein per mL resin) at a flow rate of 100 cm/h. For the 2 kD linear PEG, 20 mg Factor VIIa was loaded on to an XK26 column (Amersham Biosciences) with 40 mL Q Sepharose FF (0.5 mg protein per mg resin) at a flow rate of 100 cm/h. [0433] After loading, the column was washed with 175 mM NaCl, 10 mM glycylglycine, pH 8.6 10 column volumes) and 50 mM NaCl, 10 mM glycylglycine, pH 8.6 (2 column volumes). Elution was performed with a step gradient of 15 mM CaCl2 by using 50 mM NaCl, 10 mM glycylglycine, 15 mM CaCk, pH 8.6 (5 column volumes). The column was then washed with 1 M NaCl, 10 mM glycylglycine, pH 8.6 (5 column volumes). The effluent was monitored by absorbance at 280 nm. Fractions (5 mL) were collected during the flow-through and the two washes; 2.5 mL fractions were collected during the CaCl2 and 1M salt elutions. Fractions containing Factor VIIa were analyzed by non-reducing SDS-PAGE (Tris-glycine gels and/or NUPAGE gels) and a Colloidal Blue Staining Kit. The appropriate fractions with Factor VIIa were pooled, and the pH was adjusted to 7.2 with 4 M HC1. [0434] Factor VIIa-SA-PEG-10 kD was purified as described above, except for the following changes. EDTA (10 mM) was added to to the PEGylated Factor VIIa solution, the pH was adjusted to pH 6, and the conductivity was adjusted to 5mS/cm, at 5°C. About 20 mg of Factor VIIa-SA-PEG-10 kD was loaded on to an XK16 column (Amersham Biosciences) with 10 mL Poros 50 Micron HQ resin (no more than 2 mg protein per mL, resin) at a flow rate of 100 cm/h. After loading, the column was washed with 175 mM NaCl, 10 mM histidine pH 6 (10 column volumes) and 50 mM NaCl, 10 mM histidine, pH 6 (2 column volumes). Elution was performed with a step gradient of 20 mM CaCb in 50 mM NaCl, 10 mM histidine, pH 6 (5 column volumes). The column was then washed with 1 M NaCl, 10 mM histidine, pH 6 (5 column volumes). [0435] The anion-exchange eluate containing Factor VIIa-SA-PEG-10 kD (25mL) was concentrated to 5-7 mL by using an Amicon Ultra-15 10K centrifugal filter device, according to the manufacturer's directions (Millipore). Following concentration, size exclusion chromatography was performed. The sample (5-7 mL) was loaded onto a column containing Superdex 200 (HiLoad 16/60, prep grade; Amersham Biosciences) equilibrated in 50 mM NaCl, 10 mM glycylglycirie, 15 mM CaCb, pH 7.2 for most of the PEGyiated variants. Factor VIIa-SA-PEG-10 kD was separated from the unmodified, asialo-Factor VIIa at a flow rate of 1 mL/min, and the absorbance was monitored at 280 nm. Fractions (1 mL) containing Factor VIIa were collected and analyzed by non-reducing SDS-PAGE (Tris-glycine gels and/or NuPAGE gels) and a Colloidal Blue Staining Kit. Fractions containing the targeted PEGyiated isoform and devoid of the unmodified, asialo-Factor VIIa were pooled and concentrated to 1 mg/mL using an Amicon Ultra-15 1 OK centrifugal filter device. Protein concentration was determined from absorbance readings at 280 nm using an extinction coefficient of 1.37 (mg/mLy'cm1. EXAMPLE 4 Determination of PEGyiated Isoforms by Reversed phase HPLC analysis. [0436] PEGyiated Factor VIIa was analyzed by HPLC on a reversed-phase column (Zorbax 300SB-C3, 5 µm particle size, 2.1 x 150 mM). The eluants were A) 0.1 TFA in water and B) 0.09 % TFA in acetonitrile. Detection was at 214 nm. The gradient, flow rate, and column temperature depended on the PEG length (40 kD, 20 kD, and 10 kD PEG: 35-65 %B in 30 min, 0.5 mL/min, 45°C; 10 kD PEG: 35-60 %B in 30 min, 0.5 mL/min, 45°C; 5 kD: 40-50 %B in 40 min, 0.5 mL/min, 45°C; 2 kD: 38-43 %B in 67 min, 0.6 mL/min, 55°C). The identity of each peak was assigned based on two or more of four different pieces of evidence: the known retention time of native Factor VIIa, the SDS-PAGE migration of the isolated peak, the MALDI-TOF mass spectrum of the isolated peak, and the orderly progression of the retention time of each peak with increasing number of attached PEG. EXAMPLE 5 Determination of Site of PEG Attachment by Reversed-phase HPLC. [0437] Factor VIIa and PEGylated Factor VIIa variants were reduced by mixing sample (10 uL at a concentration of 1 mg/mL) with reducing buffer (40 uL, 50 mM NaCl, 10 mM glycylglycine, 15 mM EDTA, 8 M urea, 20 mM DTT, pH 8.6) for 15 min at room temperature. Water (50 uL) was added and the sample cooled to 4°C until injected on the HPLC ( < 12 hrs). The HPLC column, eluants, and detection were as described above for non-reduced samples. The flow rate was 0.5 mL/min and the gradient was 30-55 %B in 90 min, followed by a brief wash cycle up to 90 %B. The identity of each peak was assigned as described in Example 4. EXAMPLE 6 Factor VIIa Clotting Assay. [0438] PEGylated samples and standards were tested in duplicate, and were diluted in l00mMNaCl, 5mM CaCl2. 0.1% BSA (wt/vol), 50mM Tris, pH 7.4. The standard and samples were assayed over a range from 0.1 to 10 ng/mL. Equal volumes of diluted standards and samples were mixed with Factor VIIa deficient plasma (Diagnostica Stago), and stored on ice for no greater than 4 hours before they were assayed. [0439] Clotting times were measured with a STart4 coagulometer (Diagnostica Stago). The coagulometer measured the time elapsed until an in vitro clot was formed, as indicated by the stopping of the gentle back-and-forth movement of a magnetic ball in a sample cuvette. [0440] Into each cuvette, one magnetic ball was deposited, plus 100 uL Factor VIIa sample/deficient plasma and 100 uL of a diluted rat brain cephalin solution (stored on ice for no greater than 4 hours). Each reagent was added with 5 seconds between each well, and the final mixture was incubated for 300 seconds at 37°C. Diluted rat brain cephalin (RBC) solution was made from 2 mL RBC stock solution (1 vial RBC stock, from Haemachem, plus 10 mL 150mM NaCl) and 4 mL l00mM NaCl, 5mM CaCl2, 0.1% BSA (wt/vol), 50mM Tris, pH 7.4. [0441] At 300 seconds, the assay was started by the addition of 100 µL of a preheated (37°C) solution of soluble tissue factor (2µg/mL; amino acids 1-209) in lOOmM NaCl. 12.5mM CaCl2, 0.1% BSA (wt/vol), 50mM Tris, pH 7.4. Again, this next solution was added with a 5 second interval between samples. [0442] The clotting times from the diluted standards were used to generate a standard curve (log clot time versus log Factor VIIa concentration). The resulting linear regression from the curve was used to determine the relative clotting activities of PEGylated variants. PEGylated Factor VIIa variants were compared against an aliquotted stock of Factor VIIa. EXAMPLE 7 GlycoPEGylation of Recombinant Factor VIIa produced in BHK cells [0443] This example sets forth the PEGylation of recombinant Factor VIIa made in BHK cells. [0444] Preparation of Asialo-Factor VIIa. Recombinant Factor VIIa was produced in BHK cells (baby hamster kidney cells). Factor VIIa (14.2 mg) was dissolved at 1 mg/mL in buffer solution (pH 7.4, 0.05 M Tris, 0.15 M NaCl, 0.001 M CaCl2, 0.05% NaN3) and was incubated with 300 mU/mL sialidase (Vibrio cholera)-agarose conjugate for 3 days at 32 °C. To monitor the reaction a small aliquot of the reaction was diluted with the appropriate buffer and an IEF gel performed according to Invitrogen procedures (Figure 157). The mixture was centrifuged at 3,500 rpm and the supernatant was collected. The resin was washed three times (3x2 mL) with the above buffer solution (pH 7.4,0.05 M Tris, 0.15 M NaCl, 0.05% NaN3) and the combined washes were concentrated in a Centricon-Plus-20. The remaining solution was buffer exchanged with 0.05 M Tris (pH 7.4), 0.15 M NaCl, 0.05% NaN3 to a final volume of 14.4 mL. [0445] Preparation of Factor VIIa-SA-PEG-lkD and Factor VHa-SA-PEG-IO kD. The desialylation of Factor VIIa solution was split into two equal 7.2 mL samples. To each sample was added either CMP-SA-PEG-1 kD (7.4 mg) or CMP-SA-PEG-10 kD (7.4 mg). ST3Gal3 (1.58U) was added to both tubes and the reaction mixtures were incubated at 32°C for 96 hrs. The reaction was monitored by SDS-PAGE gel using reagents and conditions described by Invitrogen. When the reaction was complete, the reaction mixture was purified using a Toso Haas TSK-Gel-3000 preparative column using PBS buffer (pH 7.1) and collecting fractions based on UV absorption. The combined fractions containing the product were concentrated at 4°C in Centricon-Plus-20 centrifugal filters (Millipore, Bedford, MA) and the concentrated solution reformulated to yield 1.97 mg (bicinchoninic acid protein assay, BCA assay, Sigma-Aldrich, St. Louis MO) of Factor VIIa-SA-PEG. The product of the reaction was analyzed using SDS-PAGE and IEF analysis according to the procedures and reagents supplied by Invitrogen. Samples were dialyzed against water and analyzed by MALDI-TOF. EXAMPLE 8 Factor VIIa-SA-PEG-lOkD: One Pot Method [0446] Factor VIIa (5 mg diluted in the product formulation buffer to a final concentration of 1 mg/mL), CMP-SA-PEG-10 kD (l0mM, 60 uL) and A. niger enzyme ST3Gal3 (33 U/L) and 10 mM histidine, 50 mM NaCl, 20 mM CaCl2 were combined in a reaction vessel along with either 10 U/L, 1 U/L, 0.5 U/L or 0.1 U/L of sialidase (CalBiochem). The ingredients were mixed and incubated at 32°C. Reaction progress was measured by analyzing aliquots at 30 minute intervals for the first four hours. An aliquot was then removed at the 20 hour timepoint and subjected to SDS-PAGE. Extent of PEGylation was determined by removing 1 mL at 1.5, 2.5 and 3.5 hour timepoint and purifying the sample on a Poros 50HQ column. [0447] For the reaction conditions containing 10 U/L of sialidase, no appreciable amount of Factor VIIa-SA-PEG product was formed. For the reaction conditions containing 1 U/L of sialidase, about 17.6 % of the Factor VIIa in the reaction mixture was either mono or diPEGylated after 1.5 hours. This increased to 29% after 2.5 hours, and 40.3% after 3.5 hours. For the reaction conditions containing 0.5 U/L of sialidase, about 44.5 % of the Factor VIIa in the reaction mixture was either mono or diPEGylated after 3 hours, and 0.8% was triPEGylated or greater. After 20 hours, 69.4% was either mono or diPEGylated, and 18.3% was triPEGylated or greater. [0448] For the reaction conditions containing 0.1 U/L of sialidase, about 29.6% of the Factor VIIa in the reaction mixture was either mono or diPEGylated after 3 hours. After 20 hours, 71.3% was either mono or diPEGylated, and 15.1% was triPEGylated or greater. EXAMPLE 9 Preparation of Cysteine-PEG2 (2) (FORMULA REMOVED) a. Synthesis of Compound 1 {0449] Potassium hydroxide (84.2 mg, 1.5 mmol, as a powder) was added to a solution of L-cysteine (93.7mg, 0.75 mmol) in anhydrous methanol (20 L) under argon. The mixture was stirred at room temperature for 30 min, and then mPEG-O-tosylate of molecular mass 20 kilodalton (Ts; 1.0 g, 0.05 mmol) was added in several portions over 2 hours. The mixture was stirred at room temperature for 5 days, and concentrated by rotary evaporation. The residue was diluted with water (30 mL), and stirred at room temperature for 2 hours to destroy any excess 20 kilodalton mPEG-O-tosylate. The solution was then neutralized with acetic acid, the pH adjusted to pH 5.0 and loaded onto a reverse phase chromatography (C-18 silica) column. The column was eluted with a gradient of methanol/water (the product elutes at about 70% methanol), product elution monitored by evaporative light scattering, and the appropriate fractions collected and diluted with water (500 mL). This solution was chromatographed (ion exchange, XK 50 Q, BIG Beads, 300 mL, hydroxide form; gradient of water to water/acetic acid-0.75N) and the pH of the appropriate fractions lowered to 6.0 with acetic acid. This solution was then captured on a reversed phase column (C-18 silica) and eluted with a gradient of methanol/water as described above. The product fractions were pooled, concentrated, redissolved in water and freeze-dried to afford 453 mg (44%) of a white solid (1). [0450] Structural data for the compound were as follows: 1H-NMR (500 MHz; D20) 8 2.83 (t, 2H, O-C-CHz-S), 3.05 (q, 1H, S-CHH-CHN), 3.18 (q, 1H, (q, 1H, S-CHH-CHN), 3.38 (s, 3H, CH3O), 3.7 (t, OCH2CH2O), 3.95 (q, 1H, CHN). The purity of the product was confirmed by SDS PAGE. b. Synthesis ofCysteine-PEG2 (2) [0451] Triethylamine (~0.5 mL) was added dropwise to a solution of compound 1 (440 mg, 22 umol) dissolved in anhydrous CH2CI2 (30 mL) until the solution was basic. A solution of 20 kilodalton mPEG-O-p-nitrophenyl carbonate (660 mg, 33 µmol) and N-hydroxysuccinimide (3.6 mg, 30.8 umol) in CH2CI2 (20 mL) was added in several portions over 1 hour at room temperature. The reaction mixture was stirred at room temperature for 24 hours. The solvent was then removed by rotary evaporation, the residue was dissolved in water (100 mL), and the pH adjusted to 9.5 with 1.0 N NaOH. The basic solution was stirred at room temperature for 2 hours and was then neutralized with acetic acid to a pH 7.0. The solution was then loaded onto a reversed phase chromatography (C-18 silica) column. The column was eluted with a gradient of methanol/water (the product elutes at about 70% methanol), product elution monitored by evaporative light scattering, and the appropriate fractions collected and diluted with water (500 mL). This solution was chromatographed (ion exchange, XK 50 Q, BIG Beads, 300 mL, hydroxide form; gradient of water to water/acetic acid-0.75N) and the pH of the appropriate fractions lowered to 6.0 with acetic acid. This solution was then captured on a reversed phase column (C-18 silica) and eluted with a gradient of methanol/water as described above. The product fractions were pooled, concentrated, redissolved in water and freeze-dried to afford 575 mg (70 %) of a white solid (2). [0452] Structural data for the compound were as follows: JH-NMR (500 MHz; D20) 8 2.83 (t, 2H, O-C-CH2-S), 2.95 (t, 2H, O-C-CH2-S), 3.12 (q, 1H, S-CHH-CHN), 3.39 (s, 3H CH3O), 3.71 (t, OCH2CH2O). The purity of the product was confirmed by SDS PAGE. EXAMPLE 10 Factor VIIa-SA-PEG-40kD [0453] GlycoPEGylation of Factor VIIa (One Pot with Capping). GlycoPEGylation of Factor VIIa was accomplished in a one-pot reaction where desialation and PEGylation occur simultaneously, followed by capping with sialic acid. The reaction was performed in a jacketed glass vessel controlled at 32°C by a recirculating waterbath. First, the concentrated 0.2um-filtered Factor VIIa was introduced into the vessel and heated to 32°C by mixing with a stir bar for 20 minutes. A solution of sialidase was made from dry powder in lOmM histidine/50mM NaCl/20mM CaCl2, pH 6.0 at a concentration of 4,000 U/L. Once the Factor VIIa reached 32°C, the sialidase was added to the Factor VIIa, and the reaction was mixed for approximately 5 minutes to ensure a uniform solution after time which the mixing was stopped. The desialation was allowed to proceed for 1.0 h at 32°C. During the desialation reaction, the CMP-SA-PEG-40 kD was dissolved into l0mM histidine/50mM NaCl/20mM CaCl2, pH 6.0 buffer, and the concentration of was determined by UV absorbance at 271nm. After the CMP-SA-PEG-40 kD was dissolved, the CMP-SA-PEG-40 kD was added to the reaction, as well as the ST3Gal3, and the reaction was mixed for approximately 15 minutes with a stir bar to ensure a uniform solution. An additional volume of 85mL of buffer was added to make the reaction 1.0 L. The reaction was allowed to proceed without stirring for 24 hours before CMP-SA was added to a concentration of 4.3 mM to quench the reaction and cap the remaining terminal galactose residues with sialic acid. The quenching was allowed to proceed with mixing for 30 minutes at 32°C. The total volume of the reaction was 1.0 L before quenching. Timepoint samples (1 mL) were taken at 0,4.5,7.5, and 24 h, quenched with CMP-SA, and analyzed by RP-HPLC and SDS-PAGE. [0454] Purification of Factor VIIa-SA-PEG-40kD. After capping, the solution was diluted with 2.0 L of l0mM histidine, pH 6.0 that had been stored overnight at 4 °C and the sample was filtered through a 0.2um Millipak 60 filter. The resulting load volume was 3.1 L. The AEX2 chromatography was performed at 20-25°C (ambient room temperature) on an Akta Pilot system. After loading, a 10 column volumes wash with equilibration buffer was performed, and the product was eluted from the column using a 10 column volume gradient of mgCl2 which resulted in resolution of PEGylated-Factor VIIa species from unPEGylated Factor VIIa. The loading for this column was intentionally kept low, targeting < 2 mg Factor VIIa/mL resin. SDS-PAGE gels were run in addition to RP-HPLC analysis of selected fractions and pools of fractions in order to make the pool of bulk product. Pooled fractions were pH adjusted to 6.0 with 1M NaOH and stored in the cold room at 2-8°C overnight. [0455] Final Concentration/Diafiltration, aseptic filtration and aliquoting. The pooled fractions were filtered through a Millipak 20 0.2um filter and stored overnight at 2-8°C. To perform the concentration/diafiltration, a Millipore 0. lm2 30 kD regenerated cellulose membrane was used in a system fitted with a peristaltic pump and silicone tubing. The system was assembled and flushed with water, then sanitized with 0.1M NaOH for at least 1 hour, and then stored in 0.1 M NaOH until equilibration with 10 mM histidine/ 5 mM CaCy 100 mM NaCl pH 6.0 diafiltration buffer immediately before use. The product was concentrated to approximately 400 mL and then diafiltered at constant volume with approximately 5 dia volumes of buffer. The product was then concentrated to approximately 300mL and recovered after a low pressure recirculation for 5 minutes, and the membranes were rinsed with 200 mL of diafiltration buffer by a recirculation for 5 minutes. The wash was recovered with product, and another 50mL of buffer was recirculated for another 5 minutes for a final wash. The resulting bulk was approximately 510 mL, and that was filtered through a 1L vacuum filter fitted with a 0.2µm PES membrane (Millipore). The aseptically-filtered bulk was then aliquoted into 25mL aliquots in 50mL sterile falcon tubes and frozen at -80°C. Analysis of the PEGylation reaction by HPLC (Example 10) (FORMULA REMOVED) After 24 hours, the bulk product PEG-state distribution was: 0.7% unpegylated, 85.3% mono-pegylated, 11.5% di-pegylated, and 0.3% tri-pegylated. Column chromatography is the main step in the process that generates the product distribution, largely through removing unpegylated material from mono- and di-pegylated species. [0456] It is understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims. All publications, patents, and patent applications cited herein are WHAT IS CLAIMED IS: 1. A peptide conjugate comprising: a) a peptide which is covalently attached to a moiety which is a member selected from: (FORMULA REMOVED) in which R2 is a member selected from H, CH2OR7, COOR7 and OR7, wherein R7 is a member selected from H, substituted or unsubstituted alkyl and substituted or unsubstituted heteroalkyl; R3,R4,R5andR6 are members independently selected from H, substituted or unsubstituted alkyl, OR8 and NHC(0)R9; wherein R and R are independently selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, sialic acid and polysialic acid; and wherein at least one of R3, R4, R5, R6 includes a moiety which is a member selected from: (FORMULA REMOVED) in which the indices m and n are integers independently selected from 1 to 1000; A1, A2, A3, A4, A5, A6, A7, A8, A9, A10 and A11 are members independently selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, -NAI2A13, -OA12 and -SiA,2A13; wherein A12 and A13 are members independently selected from substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl. 2. The peptide conjugate of claim 1, wherein said at least one of R3, R4, R5, R6 includes a moiety which is a member selected from: (FORMULA REMOVED) 3. The peptide conjugate of claim 1, wherein said moiety is a member selected from: (FORMULA REMOVED) 4. The peptide conjugate of claim 1, wherein said peptide in the peptide conjugate is a member selected from bone morphogenetic protein 2 (BMP-2), bone morphogenetic protein 7 (BMP-7), bone morphogenetic protein 15 (BMP-15), neurotrophin-3 (NT-3), von Willebrand factor (vWF) protease, Factor VII, Factor Vila, Factor VIII, Factor IX, Factor X, Factor XI, B-domain deleted Factor VIII, vWF-Factor VIII fusion protein having full-length Factor VIII, vWF-Factor VIII fusion protein having B-domain deleted Factor VIII, erythropoietin (EPO), granulocyte colony stimulating factor (G-CSF), Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF), interferon alpha, interferon beta, interferon gamma, αl-antitrypsin (ATT, or a-1 protease inhibitor), glucocerebrosidase, Tissue-Type Plasminogen Activator (TPA), Interleukin-2 (IL-2), urokinase, human DNase, insulin, Hepatitis B surface protein (HbsAg), human growth hormone, TNF Receptor-IgG Fc region fusion protein (Enbrel™), anti-HER2 monoclonal antibody (Herceptin™), monoclonal antibody to Protein F of Respiratory Syncytial Virus (Synagis™), monoclonal antibody to TNF-α (Remicade™), monoclonal antibody to glycoprotein Ilb/IIIa (Reopro™), monoclonal antibody to CD20 (Rituxan™), anti-thrombin III (AT III), human Chorionic Gonadotropin (hCG), alpha-galactosidase (Fabrazyme™), alpha-iduronidase (Aldurazyme™), follicle stimulating hormone, beta-glucosidase, anti-TNF-alpha monoclonal antibody, glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), beta-glucosidase, alpha-galactosidase A and fibroblast growth factor