TECHNICAL FIELD
The present disclosure relates to a novel serine protease variant.
5 BACKGROUND ART
Proteases are involved in various functions such as digestion, absorption, and
defense in living organisms and are classified into serine proteases, cysteine proteases,
aspartic proteases, and metalloproteases according to the structures of active sites.
Among these, serine proteases (or serine endopeptidases) are enzymes characterized by
10 having in common an active serine residue in their active sites, which cleave peptide
bonds in proteins, in which serine serves as a nucleophilic amino acid at a protease’s
active site (Hedstrom, 2002. Chem Rev 102:4501–4524).
Serine proteases have been used in a wide variety of applications. In addition to
therapeutic applications to treat human diseases such as lysis of blood clots, serine
15 proteases are used not only as ingredients of laundry detergents and contact lens cleaners,
but also in modification of milk proteins, silk degumming, soaking of leather, unhairing,
synthesis of oligopeptides, recovery of silver from lung X-ray films, production and
improvement of feeds and foods (Korean Patent Publication No. 10-2005-0068750), and
the like.
20
DISCLOSURE
TECHNICAL PROBLEM
There is a need to develop a serine protease having improved thermal stability,
increased activity, and the like to obtain higher industrial cost-effectiveness and efficiency.
25
TECHNICAL SOLUTION
An object of the present disclosure is to provide a serine protease variant.
Another object of the present disclosure is to provide a polynucleotide encoding
the serine protease variant and a vector including the same.
30 Still another object of the present disclosure is to provide a microorganism
including one or more of the serine protease variant; a polynucleotide encoding the serine
protease variant; or a vector including the polynucleotide.
3
Still another object of the present disclosure is to provide a feed composition
including one or more of the serine protease variant or a microorganism expressing the
serine protease variant.
5 ADVANTAGEOUS EFFECTS
The serine protease variant of the present disclosure has superior activity compared
to the existing serine protease, and thus can be usefully used industrially.
BRIEF DESCRIPTION OF DRAWINGS
10 FIG. 1 illustrates the position of the residue in which a mutation is introduced into
the tertiary structure of the serine protease variant derived from Thermobifida fusca.
DETAILED DESCRIPTION OF THE INVENTION
The present disclosure will be described in detail. Meanwhile, each description
15 and embodiment disclosed in the present disclosure may be applied herein to other
descriptions and embodiments. In other words, all combinations of various components
disclosed in the present disclosure are included within the scope of the present disclosure.
Furthermore, the scope of the present disclosure should not be limited by the descriptions
provided below.
20 Additionally, those skilled in the art may recognize or be able to confirm, using no
more than routine experimentation, many equivalents to specific embodiments of the
present disclosure described in the present disclosure. Such equivalents are intended to
be encompassed in the present disclosure.
25 An aspect of the present disclosure provides a serine protease variant.
As used herein, the term “serine protease” refers to an enzyme that belongs to a
sub-group of a protease and has a proteolytic activity. Specifically, the serine protease
may be an enzyme that degrades proteins by hydrolyzing peptide bonds, and basically has
an active serine residue at active sites thereof, and more specifically an enzyme that has a
30 spatial arrangement of amino acid residues of histidine, aspartate, and serine, which can be
referred to as a catalytic triad, but is not limited thereto.
The serine protease according to the present disclosure may be derived from a
microorganism of the genus Thermobifida, the genus Nocardiopsis, the genus
Actinorugispora, or the genus Spinactinospora, but is not limited thereto. Specifically, in
4
the present disclosure, the wild type of the serine protease may be a serine protease
derived from Thermobifida fusca, Thermobifida cellulosilytica, Thermobifida halotolerans,
Actinorugispora endophytica, Spinactinospora alkalitolerans, Nocardiopsis composta, or
Nocardiopsis potens, but is not limited thereto.
5 In an embodiment, the serine protease of the present disclosure may be a
polypeptide including, consisting essentially of, or consisting of the amino acid sequence
set forth in SEQ ID NO: 31, but is not limited thereto. In an embodiment, the amino acid
sequence of SEQ ID NO: 31 may be an amino acid sequence derived from SEQ ID
NO: 40 or SEQ ID NO: 2, but is not limited thereto.
10 In an embodiment, the serine protease of the present disclosure may include,
consist essentially of, or consist of the amino acid sequence of any one of SEQ ID
NOS: 49 to 54, but is not limited thereto. In an embodiment, the amino acid sequences
of SEQ ID NOS: 49 to 54 may be derived from the amino acid sequences of any one of
SEQ ID NOS: 67 to 72, but is not limited thereto.
15 The serine protease of the present disclosure may include any sequence having the
same activity as that of the amino acid sequences described above, without limitation. In
addition, the serine protease may include, consist essentially of, or consist of the amino
acid sequence of any one of SEQ ID NOS: 31 and 49 to 54 or an amino acid sequence
having 60% or more homology or identity therewith, but is not limited thereto.
20 Specifically, the amino acid sequence may include any one of the amino acid sequences
set forth in SEQ ID NOS: 31 and 49 to 54 or an amino acid sequence having at least 60%,
61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%,
76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%,
91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% or more homology or identity with
25 any one of the amino acid sequences set forth in SEQ ID NOS: 31 and 49 to 54.
Additionally, it is obvious that any protein having an amino acid sequence including
deletion, modification, substitution, or addition in part of the sequence is within the scope
of the present disclosure as long as the amino acid sequence has such homologies or
identities described above and an effect equivalent to that of the protein.
30 In other words, although the expressions “protein or polypeptide including an
amino acid sequence set forth in a predetermined SEQ ID NO:” and “protein or
polypeptide including an amino acid sequence set forth in a predetermined SEQ ID NO:”
are used in the present disclosure, it is obvious that any protein having an amino acid
sequence including deletion, modification, substitution, or addition in part of the sequence
5
may also be used in the present disclosure as long as the protein has an activity identical or
equivalent to that of a polypeptide consisting of the corresponding amino acid sequence.
For example, it is obvious that the “polypeptide including an amino acid sequence of SEQ
ID NO: 31” belongs to the “polypeptide consisting of the amino acid sequence of SEQ ID
5 NO: 31” as long as the former has an activity identical or equivalent to that of the latter.
As used herein, the term “homology” or “identity” refers to a degree of relatedness
between two given amino acid sequences or nucleotide sequences and may be shown as a
percentage. The terms homology and identity may be used interchangeably.
Sequence homology or identity of conserved polynucleotides or polypeptides may
10 be determined by standard alignment algorithm and default gap penalties established by a
program being used may be used together. Substantially, homologous or identical
sequences may generally hybridize with each other along the entire length or at least about
50%, 60%, 70%, 80% or 90% of the entire sequence under moderate or highly stringent
conditions. Polynucleotides including degenerated codons instead of codons are also
15 considered in hybridization.
The sequence homology, similarity, or identity between any two given
polynucleotides or polypeptides may be determined using a known computer algorithm
such as “FASTA” program using default parameters as introduced by, for example,
Pearson et al. (1988) Proc. Natl. Acad. Sci. USA 85:2444. Alternatively, the Needleman–
20 Wunsch algorithm (Needleman and Wunsch, 1970, J. Mol. Biol. 48:443–453) performed
in the Needleman program of the European Molecular Biology Open Software Suite
(EMBOSS) package (Rice et al., 2000, Trends Genet. 16:276–277) (version 5.0.0 or later)
may be used to determine the same (including GCG program package (Devereux, J. et al.,
Nucleic Acids Research 12:387 (1984)), BLASTP, BLASTN, FASTA (Atschul, S. F., et al.,
25 J MOLEC BIOL 215:403 (1990); Guide to Huge Computers, Martin J. Bishop, ed.,
Academic Press, San Diego, 1994, and CARILLO et al. (1988) SIAM J Applied Math
48:1073). For example, the homology, similarity, or identity may be determined using
BLAST from The National Center for Biotechnology Information database, or ClustalW.
The homology, similarity, or identity between polynucleotides or polypeptides may
30 be determined by comparing sequence information using, for example, a GAP computer
program, such as a program introduced by Needleman et al. (1970), J Mol Biol. 48:443 as
disclosed in, for example, Smith and Waterman, Adv. Appl. Math (1981) 2:482. In brief,
the GAP program defines similarity as the number of aligned symbols (namely,
nucleotides or amino acids), which are similar, divided by the total number of symbols in a
6
shorter of two sequences. Default parameters for the GAP program may include: (1) a
binary comparison matrix (containing a value of 1 for identity and 0 for non-identity) and
a weighted comparison matrix of Gribskov et al. (1986) Nucl. Acids Res. 14:6745 as
disclosed in Schwartz and Dayhoff, eds., Atlas Of Protein Sequence And Structure,
5 National Biomedical Research Foundation, pp. 353–358 (1979) (or EDNAFULL
(EMBOSS version of NCBI NUC4.4) substitution matrix); (2) a penalty of 3.0 for each
gap and an additional 0.10 penalty for each symbol in each gap (or a gap open penalty of
10 and a gap extension penalty of 0.5); and (3) no penalty for end gaps.
In addition, the sequence homology, similarity, or identity between any two given
10 polynucleotides or polypeptides may be confirmed by comparing sequences thereof by a
southern hybridization test under defined stringent conditions, and the defined proper
hybridization conditions are within the scope of the technology and may be determined by
a method well known to those skilled in the art.
In an embodiment, the serine protease variant provided in the present disclosure
15 may refer to a variant in which an amino acid at a specific position is substituted so as to
have an enzyme activity exceeding 100% compared to that of the protein before mutation,
among the above-described proteins having the serine protease activity.
In a specific embodiment, the variant provided in the present disclosure may have
an enzyme activity exceeding 100%, specifically an increased enzymatic activity of about
20 110%, about 120%, about 130%, about 140%, about 150%, about 160%, about 170%,
about 180%, about 190%, or about 200% or more compared to that of the wild-type
enzyme including the amino acid sequence of any one of SEQ ID NOS: 31 and 49 to 54,
but is not limited thereto.
The term “about” is a range including all of ±0.5, ±0.4, ±0.3, ±0.2, ±0.1, and the
25 like, and includes all numerical values in the range equivalent to or similar to the
numerical value following the term about, but is not limited thereto.
As used herein, the term “variant” refers to a polypeptide obtained by conservative
substitution and/or modification of one or more amino acids different from that of the
recited sequence while retaining the functions or properties of the protein. A variant is
30 different from the identified sequence due to substitution, deletion, or addition of several
amino acids. Such a variant may generally be identified by modifying one of the
polypeptide sequences and evaluating properties of the modified polypeptide. That is,
the ability of a variant may be enhanced, unchanged, or diminished compared to that of a
native protein.
7
In addition, some variants may include variants in which one or more portions
such as an N-terminal leader sequence or transmembrane domain are removed. Other
variants may include variants in which a portion is removed from or added to the Nand/or C-terminus of a mature protein.
5 The term “variant” may also be used interchangeably with other terms such as
modification, modified protein, modified polypeptide, mutant, mutein, and divergent, and
any terms used to indicate variation may also be used without limitation.
The variant may have an activity of the modified protein enhanced compared to
that of natural wild-type or non-modified proteins, but is not limited thereto.
10 As used herein, the term “conservative substitution” refers to substitution of one
amino acid with another amino acid having similar structural and/or chemical properties.
For example, the variant may have one or more conservative substitutions while still
retaining one or more biological activities. Such amino acid substitution may generally
occur based on similarity of polarity, charge, solubility, hydrophobicity, hydrophilicity,
15 and/or amphipathic nature of a residue. For example, among electrically charged amino
acids with side chains, positively charged (basic) amino acids include arginine, lysine, and
histidine and negatively charged (acidic) amino acids include glutamate and aspartate;
among uncharged amino acids with side chains, nonpolar amino acids include glycine,
alanine, valine, leucine, isoleucine, methionine, phenylalanine, tryptophan and proline and
20 polar or hydrophilic amino acids include serine, threonine, cysteine, tyrosine, asparagine
and glutamine; and among the amino acids, aromatic amino acids include phenylalanine,
tryptophan and tyrosine. The variant may also include deletion or addition of amino
acids having minimum influence on the properties and secondary structure of a
polypeptide. For example, a polypeptide may be conjugated to a signal (or leader)
25 sequence of the N-terminus of a protein involved in transfer of the protein cotranslationally or post-translationally. The polypeptide may also be conjugated to
another sequence or linker to identify, purify, or synthesize the polypeptide
As used herein, the term “serine protease variant” refers to a polypeptide including
substitution of one or more amino acids in an amino acid sequence of a polypeptide
30 having the serine protease activity.
The serine protease variant according to the present disclosure may include
substitution of amino acids at positions corresponding to the 12th amino acid and/or 116th
amino acid from the N-terminus of the amino acid sequence of SEQ ID NO: 31 with other
amino acids. Specifically, the serine protease variant may include substitution of amino
8
acids corresponding to the 12th amino acid and/or 116th amino acid of SEQ ID NO: 31,
and may include an amino acid sequence having 60% or more and less than 100%
homology or identity with the amino acid sequence of any one of SEQ ID NOS: 31 and 49
to 54.
5 In an embodiment, the serine protease variant of the present disclosure may
include substitution of amino acids at positions corresponding to the 12th amino acid
and/or 116th amino acid of SEQ ID NO: 31, and may have 60% or more, for example,
61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%,
76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%,
10 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% or more, and less than 100%
homology or identity with the amino acid sequence of any one of SEQ ID NOS: 31 and 49
to 54, but is not limited thereto.
Meanwhile, since the 12th amino acid and 116th amino acid from the N-terminus
of SEQ ID NO: 31 correspond to the 12th amino acid and 116th amino acid from the N15 terminus of SEQ ID NOS: 49 to 54, the description of the positions of the amino acids
based on SEQ ID NO: 31 may be equally applied to the 12th amino acid and 116th amino
acid of the amino acid sequence of any one of SEQ ID NOS: 49 to 54.
In an embodiment, the serine protease variant of the present disclosure may
include substitution of amino acids at positions corresponding to the 12th amino acid
20 and/or 116th amino acid of SEQ ID NO: 54, and may include an amino acid sequence
having 60% or more, for example, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%,
70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%,
85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%
or more, and less than 100% homology or identity with the amino acid sequence of any
25 one of SEQ ID NOS: 52 to 54. Specifically, the serine protease variant may include
substitution of an amino acid at a position corresponding to the 12th amino acid of SEQ
ID NO: 54, and may have 60% or more, for example, 61%, 62%, 63%, 64%, 65%, 66%,
67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%,
82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%,
30 97%, 98%, or 99% or more, and less than 100% homology or identity with the amino acid
sequence of SEQ ID NO: 54, but is not limited thereto.
In an embodiment, the serine protease variant of the present disclosure may be a
protein in which amino acids corresponding to position 12, position 116, or positions 12
and 116 from the N-terminus in the amino acid sequence of any one selected from SEQ ID
9
NOS: 31 and 49 to 54 are all substituted with other amino acids. The “other amino acids”
refer to amino acids different from those before the substitution, and are not limited as
long as they are amino acids other than the amino acids before the substitution.
In an embodiment, the serine protease variant according to the present disclosure
5 may be a variant in which phenylalanine at position 12 in the amino acid sequence of any
one selected from SEQ ID NOS: 31 and 49 to 51 is substituted with glycine, alanine,
arginine, aspartate, cysteine, glutamate, asparagine, glutamine, histidine, proline, serine,
tyrosine, isoleucine, leucine, lysine, tryptophan, valine, methionine, or threonine; and/or
asparagine at position 116 is substituted with glycine, alanine, arginine, aspartate, cysteine,
10 glutamate, glutamine, histidine, proline, serine, tyrosine, isoleucine, leucine, lysine,
phenylalanine, tryptophan, valine, methionine, or threonine, but is not limited thereto.
In an embodiment, the serine protease variant according to the present disclosure
may be a variant in which proline at position 12 in the amino acid sequence of any one
selected from SEQ ID NOS: 52 to 54 is substituted with phenylalanine, glycine, alanine,
15 arginine, aspartate, cysteine, glutamate, asparagine, glutamine, histidine, serine, tyrosine,
isoleucine, leucine, lysine, tryptophan, valine, methionine, or threonine; and/or asparagine
at position 116 is substituted with glycine, alanine, arginine, aspartate, cysteine, glutamate,
glutamine, histidine, proline, serine, tyrosine, isoleucine, leucine, lysine, phenylalanine,
tryptophan, valine, methionine, or threonine, but is not limited thereto.
20 Specifically, the variant may be a protein in which an amino acid corresponding to
position 12 in the amino acid sequence of any one selected from SEQ ID NOS: 31 and 49
to 54 is substituted with tyrosine (Y), serine (S), alanine (A), or arginine (R); an amino
acid corresponding to position 116 is substituted with aspartate (D), serine (S), threonine
(T), or glycine (G); or amino acids at positions 12 and 116 in the amino acid sequence of
25 SEQ ID NO: 31 are substituted with tyrosine (Y) and aspartate (D), tyrosine (Y) and
serine (S), serine (S) and aspartate (D), serine (S) and threonine (T), or alanine (A) and
glycine (G), respectively, but is not limited thereto. In an embodiment, the serine
protease variant may be a variant in which proline at position 12 in the amino acid
sequence of any one selected from SEQ ID NOS: 52 to 54 is substituted with tyrosine,
30 alanine, serine or arginine, but is not limited thereto.
It is obvious that the variant, in which the amino acids at position 12 and/or
position 116 in the amino acid sequence of any one selected from SEQ ID NOS: 31 and 49
to 54 are substituted with other amino acids, includes variants in which the amino acids
corresponding to the positions are substituted with other amino acids.
10
Additionally, the variant also includes variants in which the amino acids at
positions corresponding to the 12th amino acid and/or 116th amino acid from the Nterminus of the amino acid sequence of any one selected from SEQ ID NOS: 31 and 49 to
54 are substituted with other amino acids in the above-described amino acid sequence set
5 forth in any one selected from SEQ ID NOS: 31 and 49 to 54 or an amino acid sequence
having at least 60% or more, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%,
70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%,
85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%
or more homology or identity with the amino acid sequence of any one selected from SEQ
10 ID NOS: 31 and 49 to 54.
In an embodiment, among the variants, the variant, in which the amino acids at
positions corresponding to the 12th amino acid and/or 116th amino acid in the amino acid
sequence of SEQ ID NO: 31 are substituted with other amino acids, may include, consist
essentially of, or consist of an amino acid sequence set forth in any one selected from SEQ
15 ID NOS: 32 to 39, but is not limited thereto.
In an embodiment, among the variants, the variant, in which the amino acids at
positions corresponding to the 12th amino acid and/or 116th amino acid in the amino acid
sequence of SEQ ID NO: 49 are substituted with other amino acids, may include, consist
essentially of, or consist of the amino acid sequence of SEQ ID NO: 55 or 56, but is not
20 limited thereto.

WE CLAIM:
1. A serine protease variant comprising substitution of an amino acid corresponding
to position 12 based on an amino acid sequence set forth in SEQ ID NO: 54 and an
amino acid sequence having 60% or more and less than 100% homology or
identity with an amino acid sequence set forth in SEQ ID NO: 54.
2. The serine protease variant according to claim 1, wherein the variant further
comprises substitution of an amino acid corresponding to position 116 based on an
amino acid sequence set forth in SEQ ID NO: 54.
3. The serine protease variant according to claim 1, wherein the variant has 75% or
more and less than 100% homology or identity with an amino acid sequence set
forth in SEQ ID NO: 54.
4. The serine protease variant according to claim 1, wherein an amino acid
corresponding to position 12 is substituted with a hydrophilic amino acid, a
nonpolar amino acid, or a basic amino acid.
5. The serine protease variant according to claim 1, wherein an amino acid
corresponding to position 12 is substituted with tyrosine (Y), alanine (A), serine
(S), or arginine (R).
6. The serine protease variant according to claim 1, wherein the serine protease
variant comprises substitution of an amino acid corresponding to position 201
based on an amino acid sequence set forth in SEQ ID NO: 71 or 72.
7. The serine protease variant according to claim 1, wherein the serine protease
variant comprises substitution of an amino acid corresponding to position 203
based on an amino acid sequence set forth in SEQ ID NO: 70.
8. The serine protease variant according to claim 1, wherein the serine protease
variant has at least 60% or more and less than 100% sequence homology to an
amino acid sequence set forth in any one of SEQ ID NOS: 70 to 72.
38
9. The serine protease variant according to claim 2, wherein an amino acid
corresponding to position 116 is substituted with a hydrophilic amino acid, a
nonpolar amino acid, or an acidic amino acid.
10. The serine protease variant according to claim 2, wherein an amino acid
corresponding to position 116 is substituted with aspartate (D), serine (S),
threonine (T), or glycine (G).
11. A composition comprising the serine protease variant according to any one of
claims 1 to 10.
12. A polynucleotide encoding the serine protease variant according to any one of
claims 1 to 10.
13. A vector comprising the polynucleotide according to claim 12.
14. A host cell comprising one or more of the serine protease variant according to any
one of claims 1 to 10; a polynucleotide encoding the variant; or a vector including
the polynucleotide.
15. A composition comprising one or more of the serine protease variant according to
any one of claims 1 to 10; or a microorganism expressing the variant.