Family S1

Family

Summary Holotypes Alignment Tree Genomes Structure Literature H-seq M-seq

S1A

Summary Holotypes Alignment Tree Genomes Literature

S1B

Summary Holotypes Alignment Tree Genomes Literature

S1C

Summary Holotypes Alignment Tree Genomes Literature

S1D

Summary Holotypes Alignment Tree Genomes Literature

S1E

Summary Holotypes Alignment Tree Genomes Literature

S1F

Summary Holotypes Alignment Tree Genomes Literature

Summary for family S1

NamePeptidase family S1 (chymotrypsin family)
Family type peptidaseS01.001 - chymotrypsin A (cattle-type) (Bos taurus), MEROPS Accession MER0000002 (peptidase unit: 34-263)
Content of familyPeptidase family S1 contains serine endopeptidases.
History Identifier created: Biochem.J. 290:205-218 (1993)
Family S1 is the largest of all of the peptidase families, by both the number of proteins that have been sequenced and the number of distinct peptidase activities.
Catalytic typeSerine
Active siteThe peptidases of family S1 contain the catalytic triad His, Asp and Ser found in all members of subclan PA(S). Activity has been claimed for human testes-specific protein TSP50 (S01.208) which has the serine replaced by threonine (Xu et al., 2007), although the serine is conserved for this protein from many other vertebrates.
Activities and specificitiesAll of the characterised peptidases of the chymotrypsin family are endopeptidases. There are also a number of non-peptidase homologues in which catalytic residues have been replaced. There are three main activity types: trypsin-like where there is cleavage of amide substrates following Arg or Lys at P1, chymotrypsin-like where cleavage occurs following one of the hydrophobic amino acids at P1, and elastase-like with cleavage following an Ala at P1. Substrate specificity in family S1 is dependent only on what is in the P1 position. The majority of the peptidases of this family enter the secretory pathway and have an N-terminal signal peptide. They are synthesized as precursors with an N-terminal extension that is cleaved to form the active enzyme. Activation does not always require the propeptide to be removed; in the blood coagulation factors cleavage is all that is required, with the propeptide remaining bound by disulfide bridges as the heavy chain. Cleavage of the precursor is essential to enable a structural rearrangement to take place with the newly exposed N-terminus (usually Ile or Val) which binds to the Asp next to the active site Ser in the GDSGG motif. The N-terminal extension varies in size from just two residues in cathepsin G (S01.133) to longer ones containing hundreds of amino acids.
InhibitorsThere are many natural protein inhibitors of the chymotrypsin family. These include inhibitors from the ovomucoid (I1), aprotinin (I2) and Bowman-Birk (I12) inhibitor families. The serpins also inhibit a number of peptidases in family S1. Other non-natural inhibitors of the chymotrypsin family include phenylmethylsulfonyl fluoride (PMSF), diisopropylfluoro phosphate (DFP), leupeptin, p-tosyl-L-arginine methyl ester (TAME) and N-alpha-tosyl-L-lysine chloromethyl ketone (TLCK).
Molecular structureA number of the tertiary structures have been solved for the peptidases of the chymotrypsin family. The tertiary structure of chymotrypsin is a two domain structure, each containing an open-ended beta barrel at right angles to each other. This crossing pattern of the beta strands in the barrel has been described as a "Greek Key". The N-terminal extension of the chymotrypsin family peptidases contains domains that are found almost exclusively in the peptidases of this family. Apple domains are known only in the chymotrypsin family. Also, kringle domains are mainly found in these peptidases, but some do occur in receptor kinases.
ClanPA
SubclanPA(S)
Basis of clan assignmentType family of clan PA.
Distribution of family Bacteria details  
Archaea details  
Protozoa details  
Fungi details  
Plants details  
Animals details  
Viruses details  
Biological functionsThe peptidases of family S1 play many roles. These include intestinal digestion (trypsin and chymotrypsin), IgA-mediated immune response (tryptase and chymase from mast cells and the granzymes found in cytotoxic cells), and the role of the snake and easter peptidases in the dorsal-ventral signalling pathway of drosophila.
Pharmaceutical and biotech relevanceThe peptidases of family S1 have huge potential as drug targets. Areas of interest include blood coagulation pathway and the complement activation. Chymotrypsin has been used to dissolve a suspensory ligament of the lens in the eye to aid in the surgical removal of the lens because of cataract. It is also used in the limited proteolysis of proteins for sequencing.
Statistics for family S1Sequences:57900
Identifiers:691
Identifiers with PDB entries:112
Downloadable files Sequence library (FastA format)
Sequence alignment (FastA format)
Phylogenetic tree (Newick format)
Subfamily S1A
Name Peptidase subfamily S1A
Subfamily type peptidase S01.001 - chymotrypsin A (cattle-type) (Bos taurus), MEROPS Accession MER0000002 (peptidase unit: 34-263)
Active site residues H75 D120 S213 
Statistics Sequences: 40765
Identifiers: 616
Identifiers with PDB entries: 88
Other databases CATH 2.40.10.10
HOMSTRAD sermam
HSSP 8gch
INTERPRO IPR001314
PANTHER PTHR24250
PFAM PF00089
PFAM PF03761
PFAM PF13365
SCOP 50514
Downloadable files Sequence library [FastA format]
Sequence alignment [FastA format]
Phylogenetic tree [Newick format]
Peptidases and Homologues MEROPS ID Structure
chymotrypsin A (cattle-type)S01.001Yes
mast cell peptidase 2 (Mus musculus)S01.003-
Cma2 g.p. (Mus musculus)S01.004-
mast cell peptidase 4 (Rattus)S01.005-
mast cell peptidase 10 (Rattus)S01.008-
mast cell peptidase 8 (Rattus)S01.009-
granzyme B (Homo sapiens-type)S01.010Yes
testisinS01.011-
mast cell peptidase 3 (Rattus)S01.012-
Nudel peptidaseS01.013-
kallikrein-related peptidase 5S01.017Yes
scolexinS01.018-
corinS01.019-
kallikrein-related peptidase 12S01.020-
DESC1 peptidaseS01.021Yes
ovochymase domain 1S01.022-
flavoxobinS01.023Yes
ovochymase domain 2S01.024-
mast cell peptidase 6 (mouse numbering)S01.025-
mast cell peptidase 7 (mouse numbering)S01.026-
tryptase gamma 1S01.028-
kallikrein-related peptidase 14S01.029-
granzyme NS01.030-
peptidase 9 (Dermatophagoides-type)S01.031-
factor VII-activating peptidaseS01.033-
transmembrane peptidase, serine 4S01.034-
brachyurin-TS01.035Yes
granzyme OS01.036-
kallikrein 1-related peptidase b5 (Mus sp.)S01.037-
kallikrein 1-related peptidase b21 (Mus musculus)S01.038-
kallikrein 1-related peptidase b22 (Mus musculus)S01.039-
chymotrypsin-like enzyme (Lepidoptera)S01.040-
kallikrein 1-related peptidase b11S01.041-
intestinal serine peptidase (rodent)S01.042-
TESP2 peptidase (Mus musculus)S01.045-
human airway trypsin-like peptidaseS01.047-
Xesp-1 g.p. (Xenopus sp.)S01.048-
Xesp-2 g.p. (Xenopus laevis)S01.049-
XMT-SP1 g.p. (Xenopus laevis)S01.050-
kallidin-releasing enzyme (Bitis arietans)S01.052-
tryptase delta 1 (Homo sapiens)S01.054-
trypsin 5 (mouse numbering)S01.055-
trypsin 8 (mouse numbering)S01.057-
trypsin 9 (mouse numbering)S01.058-
trypsin 10 (mouse numbering)S01.059-
trypsin 11 (mouse numbering)S01.060-
trypsin 12 (mouse numbering)S01.061-
trypsin 15 (mouse numbering)S01.062-
trypsin 16 (mouse numbering)S01.063-
trypsin 20 (mouse numbering)S01.064-
kallikrein 1-related peptidase b8S01.067-
kallikrein 1-related peptidase b24 (Mus musculus)S01.069-
kallikrein 1-related peptidase b26 (Mus musculus)S01.070-
kallikrein 1-related peptidase b9 (Mus musculus)S01.071-
matriptase-3S01.072-
kallikrein 1-related peptidase b27 (Mus musculus)S01.073-
marapsinS01.074-
tryptase-6S01.075-
ovochymase-1 domain 1S01.078-
transmembrane peptidase, serine 3S01.079-
kallikrein-related peptidase 15S01.081-
spermosin (Halocynthia roretzi)S01.082-
Mername-AA031 peptidaseS01.085-
30kP peptidase A (Bombyx-type)S01.086-
TMPRSS13 peptidaseS01.087-
Mername-AA038 peptidaseS01.088-
hypodermin BS01.090-
natural killer cell peptidase 1 (Rattus norvegicus)S01.091Yes
trypsin Va (rodent)S01.092-
trypsin Vb (Rattus norvegicus)S01.093-
trypsin 1 (Rattus-type)S01.094Yes
vascular chymase (Rattus norvegicus)S01.095-
granzyme B (Equus-type)S01.096-
granzyme-like protein 1 (Rattus norvegicus)S01.097-
Prss43 peptidaseS01.099-
trypsin (Streptomyces griseus-type)S01.101Yes
trypsin (Streptomyces erythraeus-type)S01.102-
trypsin (fungal)S01.103Yes
1700007n14rik protein (Mus musculus) and similarS01.104-
Mername-AA204 peptidaseS01.105-
Prss44 peptidaseS01.106-
Mername-AA206 peptidaseS01.107-
tryptase-5S01.108-
trypsin alpha (insect)S01.110-
hypodermin AS01.111-
cocoonaseS01.112-
vitellin-degrading peptidase (Bombyx-type)S01.113-
trypsin theta (insect)S01.114-
trypsin iota (insect)S01.115-
trypsin zeta (insect)S01.116-
trypsin eta (insect)S01.117-
tryptase (mammalian, non-Homo sapiens-type)S01.118-
trypsin-2 type CS01.119Yes
trypsin-2 type BS01.120-
hypodermin CS01.121Yes
brachyurin-CS01.122Yes
euphauseraseS01.123-
trypsin YS01.124-
trypsin-1 (fish)S01.125Yes
trypsin-3 (fish)S01.126Yes
cationic trypsin (Homo sapiens-type)S01.127Yes
trypsin (Petromyzon-type)S01.128-
trypsin 4 (Mus musculus) and similarS01.129-
trypsin (mosquito type)S01.130-
elastase-2S01.131Yes
mannan-binding lectin-associated serine peptidase-3S01.132-
cathepsin GS01.133Yes
myeloblastinS01.134Yes
granzyme AS01.135Yes
granzyme B, rodent-typeS01.136Yes
granzyme CS01.137Yes
granzyme MS01.139Yes
chymase (Homo sapiens-type)S01.140Yes
mast cell peptidase 1 (Rattus-type)S01.141Yes
duodenaseS01.142Yes
tryptase alphaS01.143Yes
mastinS01.145-
granzyme KS01.146Yes
granzyme HS01.147-
granzyme JS01.148-
mast cell peptidase 4 (mouse numbering)S01.149-
mast cell peptidase 5 (mouse numbering)S01.150Yes
trypsin 1S01.151Yes
chymotrypsin BS01.152Yes
elastase-1S01.153Yes
pancreatic endopeptidase ES01.154-
pancreatic elastase IIS01.155Yes
enteropeptidaseS01.156Yes
chymotrypsin CS01.157Yes
prostasinS01.159Yes
kallikrein 1S01.160Yes
kallikrein-related peptidase 2S01.161-
kallikrein-related peptidase 3S01.162Yes
kallikrein 1-related peptidase b16 (Mus musculus)S01.163-
kallikrein 1-related peptidase b1S01.164-
kallikrein 1-related peptidase c10 (Rattus norvegicus)S01.165-
proteolytic lectin (Anopheles-type)S01.166-
kallikrein 1 (Mus musculus)S01.167-
chymotrypsin m-type 2 (insect)S01.168-
kallikrein 1-related peptidase b3S01.170Yes
kallikrein 1 (Equus caballus)S01.171Yes
kallikrein 1-related peptidase c2 (Rattus norvegicus)S01.172Yes
kallikrein 13 (Mus musculus)S01.173Yes
mesotrypsinS01.174Yes
batroxobinS01.176-
crotalaseS01.177-
ancrodS01.178-
bothrombinS01.179Yes
platelet-aggregating venom peptidaseS01.180Yes
bilineobinS01.181-
trypsin IV (Rattus norvegicus)S01.183-
factor V activator (Daboia russellii)S01.184-
snake venom plasminogen activatorS01.186Yes
peptidase 6 (Dermatophagoides sp.)S01.187-
capillary permeability-increasing enzyme-2 (Gloydius-type)S01.188-
complement component C1r-like peptidaseS01.189-
tissue kallikrein (Mastomys natalensis)S01.190-
complement factor DS01.191Yes
complement component activated C1rS01.192Yes
complement component activated C1sS01.193Yes
complement component C2aS01.194Yes
mast cell protease 8-like 2 (Rattus norvegicus)S01.195-
complement factor BbS01.196Yes
mast cell protease 8-like 3 precursor (Rattus norvegicus)S01.197-
mannan-binding lectin-associated serine peptidase 1S01.198Yes
complement factor IS01.199-
Snake peptidase (Insecta)S01.200-
Easter peptidaseS01.201-
Gastrulation-defective peptidaseS01.202-
melanization peptidase-2 (Drosophila melanogaster) and similarS01.203-
prophenoloxidase-activating peptidase-IS01.204Yes
pancreatic endopeptidase E form BS01.205-
pancreatic elastase IIBS01.206-
9930019B18Rik proteinS01.207-
complement component C1rB (Mus musculus) and similarS01.209-
complement component C1sB (Mus musculus)S01.210-
coagulation factor XIIaS01.211Yes
plasma kallikreinS01.212Yes
coagulation factor XIaS01.213Yes
coagulation factor IXaS01.214Yes
coagulation factor VIIaS01.215Yes
coagulation factor XaS01.216Yes
thrombinS01.217Yes
protein C (activated)S01.218Yes
coagulation factor C (Limulus, {Tachypleus}), activatedS01.219-
coagulation factor B (Limulus, {Tachypleus}), activatedS01.220-
clotting enzyme (Tachypleus-type)S01.221-
coagulation factor G, activatedS01.222-
acrosinS01.223Yes
hepsinS01.224Yes
Stubble peptidase (Insecta)S01.225-
hepatocyte growth factor activatorS01.228Yes
mannan-binding lectin-associated serine peptidase 2S01.229Yes
Prss47 peptidaseS01.230-
urokinase-type plasminogen activatorS01.231Yes
t-plasminogen activatorS01.232Yes
plasminS01.233Yes
peptidase 3 (Dermatophagoides-type)S01.234-
acutobinS01.235-
kallikrein-related peptidase 6S01.236Yes
neurotrypsinS01.237-
plasminogen activator (Desmodus-type)S01.239Yes
oviductinS01.240-
lumbrokinaseS01.243Yes
kallikrein-related peptidase 8S01.244Yes
ovochymase domain 3S01.245-
kallikrein-related peptidase 10S01.246-
epitheliasinS01.247-
putative peptidase similar to natural killer cell peptidase 1 (Rattus norvegicus)S01.248-
testis serine peptidase 6S01.250-
kallikrein-related peptidase 4S01.251Yes
proseminS01.252-
halystaseS01.253Yes
mast cell peptidase 8 (Mus musculus)S01.254-
chymopasinS01.256-
kallikrein-related peptidase 11S01.257-
trypsin-2 type AS01.258-
B1598 peptidaseS01.260-
kallikrein 1-related peptidase c12 (Rattus norvegicus)S01.287-
kallikrein 1-related peptidase c8 (Rattus norvegicus)S01.288-
arginine esterase (Canis-type)S01.289-
renal kallikrein (Mastomys natalensis)S01.290-
TMPRSS12 peptidaseS01.291-
HAT-like putative peptidase 2S01.292-
HAT-like 3 peptidaseS01.294-
peptidase similar to prostinS01.297-
trypsin CS01.298-
Mername-AA175 peptidaseS01.299-
kallikrein-related peptidase 7S01.300Yes
matriptaseS01.302Yes
mast cell peptidase-11 (rodent)S01.303-
mast cell peptidase-9 (Mus musculus)S01.304-
prophenoloxidase-activating peptidase (Bombyx-type)S01.305-
kallikrein-related peptidase 13S01.306-
kallikrein-related peptidase 9S01.307-
matriptase-2S01.308-
LCLP peptidaseS01.311-
spinesinS01.313-
strypsin-1S01.314-
strypsin-2S01.315-
CG4386 peptidaseS01.316-
Prss42 peptidaseS01.317-
marapsin-2S01.318-
neutrophil serine peptidase 4S01.319Yes
ovochymase-2S01.320-
HAT-like 4 peptidaseS01.321-
ovochymase 1 domain 1S01.322-
Mername-AA184 peptidaseS01.324-
epidermis-specific SP-like putative peptidaseS01.325-
testis serine peptidase 5S01.326-
Mername-AA258 peptidaseS01.327-
catroxase IS01.330-
pallabinS01.331-
pallabin 2S01.332-
pallaseS01.333-
alpha-fibrinogenase (Vipera-type)S01.334-
calobinS01.335-
catroxobin IS01.336-
cerastobinS01.337-
salmobinS01.338-
cerastotinS01.339-
serpentokallikrein-1 (Trimeresurus mucrosquamatus)S01.340-
brevinaseS01.341-
cerastocytinS01.342-
mucofibrase 1S01.343-
mucofibrase 4S01.344-
mucofibrase 5S01.345-
okinaxobin IS01.346-
contortrixobinS01.347-
acubinS01.348-
acubin2S01.349-
salmonaseS01.350-
elegaxobin (Trimeresurus elegans)S01.352-
KN-BJ peptidase 1 (Bothrops jararaca)S01.353-
KN-BJ peptidase 2 (Bothrops jararaca)S01.354-
elegaxobin II (Trimeresurus elegans)S01.355-
afaacytin (Cerastes cerastes)S01.356-
polyserase-IA unit 1S01.357-
polyserase-IA unit 2S01.358-
complement component C1sA (Mus musculus)S01.360-
testis serine peptidase 2 (human-type)S01.362-
hypothetical acrosin-like peptidase (Homo sapiens)S01.363-
HAT-like 5 peptidaseS01.365-
HlSP-type peptidaseS01.366-
putative peptidase, serine-like 1 (Mus musculus)S01.368-
putative peptidase similar to cattle testicular serine protease 2S01.371-
TRAF3 interacting protein 3S01.372-
Mername-AA268 putative granzymeS01.373-
polyserase-3 unit 1S01.374-
polyserase-3 unit 2S01.375-
peptidase similar to tryptophan/serine proteaseS01.376-
TPA: mast cell protease 4-like 1 precursor (Rattus norvegicus)S01.377-
similar to natural killer cell protease 7 (Rattus norvegicus)S01.379-
similar to natural killer cell protease 1 (Rattus norvegicus)S01.380-
S01.381-
similar to mast cell protease 8 (Rattus norvegicus)S01.382-
mast cell protease 1-like 2 (Rattus norvegicus)S01.383-
mast cell protease 1-like 3 (Rattus norvegicus)S01.384-
mast cell protease 1-like 4 (Rattus norvegicus)S01.385-
similar to implantation serine protease 2 (Rattus-type)S01.386-
Mername-AA255 peptidaseS01.387-
hypothetical protein LOC691670 (Rattus norvegicus)S01.389-
putative peptidase similar to plasma kallikrein (rodent)S01.390-
ovochymase (Branchiostoma-type)S01.391-
allergen Sar s 3S01.392-
hypothetical peptidase LOC100287362S01.394-
hypothetical peptidase LOC138652S01.395-
coagulation factor Xa (Tropidechis-type)S01.396-
granzyme DS01.398-
granzyme ES01.399-
granzyme F (Mus musculus)S01.401-
granzyme G (Mus musculus)S01.402-
granzyme RNKP-7 (Rattus sp.)S01.404-
kallikrein 1 (Rattus sp.)S01.405-
kallikrein 1-related peptidase c7 (Rattus sp.)S01.406-
kallikrein 1-related peptidase c9 (Rattus sp.)S01.407-
elastase AS01.408-
blarinasinS01.409-
kallikrein 1-related peptidase c4 (Rattus norvegicus)S01.410-
kallikrein 1-related peptidase c3 (Rattus norvegicus)S01.411-
prophenoloxidase-activating peptidase (Pacifastacus leniusculus)S01.413-
polyserase-2 unit 1S01.414-
Mername-AA123 peptidaseS01.415-
Prss41 g.p. (Mus musculus)S01.417-
kallikrein 5-like peptidaseS01.418-
plasma kallikrein-like peptidaseS01.419-
prothrombin activator (Lonomia sp.)S01.420-
Persephone peptidaseS01.421-
fibrinolytic enzyme A (Annelida-type)S01.422Yes
serine peptidase SP-28 (Ctenocephalides felis)S01.424-
trocarin DS01.425-
hopsarin D (Hoplocephalus stephensi)S01.426-
prophenoloxidase-activating peptidase (Manduca-type)S01.427-
LV-Ka peptidaseS01.428-
factor V activating enzyme (Vipera lebetina) and similarS01.429-
gabonase (Bitis gabonica)S01.430-
rhombeobin (Lachesis muta rhombeata )S01.432-
peptidase A (Bothrops-type)S01.433-
gilatoxinS01.435-
HAT-like 2 peptidaseS01.436-
chymotrypsin B (Gadus-type)S01.437-
fire ant chymotrypsinS01.438Yes
cortical granule serine peptidase 1 (Strongylocentrotus sp.)S01.439-
hemolymph proteinase 14S01.444-
pseutarin CS01.446-
CLIPB14-type peptidaseS01.448-
CLIPB15 peptidaseS01.449-
blarina toxin (Blarina brevicauda)S01.452-
BthaTL peptidaseS01.456-
CG17012 peptidaseS01.457-
chymase 1 (Mus musculus-type)S01.458-
kallikrein 1-related peptidase c6 (Rattus norvegicus)S01.460-
tequila peptidaseS01.461-
Spatzle-processing enzyme (Drosophila sp.)S01.462-
LV-PA peptidase (Lachesis muta muta)S01.463-
OET-03 peptidase (Homarus americanus)S01.464-
granzyme-like protein III (Rattus norvegicus)S01.465-
ACC-C peptidaseS01.466Yes
hemolymph proteinase 21S01.467-
Mcpt2-rs2a peptidase (Mus musculus)S01.468-
Mcpt2-rs2c peptidase (Mus musculus)S01.469-
Mcpt8-rs4 peptidase (Mus musculus)S01.471-
late trypsinS01.478-
peptidase Ba III 4 (Bothrops atrox)S01.479-
harobinS01.481-
Mername-AA247 peptidaseS01.483-
CTLP-1-type peptidaseS01.484-
hCG2041452-like proteinS01.487-
hCG22067 putative peptidaseS01.488-
kallikrein 10 (rodent-type)S01.489-
BJ-48 peptidase (Bothrops jararacussu)S01.490-
proteolytic lectin (Glossina-type)S01.493-
tunicate retinoic acid-inducible modular proteaseS01.495-
Dav-X peptidase (Deinagkistrodon acutus)S01.496-
Haly-2 peptidase (Gloydius-type)S01.497-
ovigerous-hair stripping substanceS01.498-
Grass peptidase (Insecta)S01.502Yes
TmMSP peptidaseS01.505-
TmSAE peptidaseS01.506-
TmSPE peptidase (Tenebrio-type)S01.507-
ModSP peptidase (Drosophila sp.)S01.508-
gloshedobin (Gloydius shedaoensis)S01.509-
allergen Per a 10 (Periplaneta americana)S01.510-
Bi-VSP peptidase (Bombyx ignitus)S01.511-
ascidian acrosinS01.512-
PRSS56 peptidaseS01.514-
VesA peptidase (Vibrio cholerae)S01.515-
VesB peptidase (Vibrio cholerae)S01.516-
VesC peptidase (Vibrio cholerae)S01.517-
VvpS peptidase (Vibrio vulnificus)S01.518-
CLSP2 g.p. (Aedes aegypti)S01.519-
chymotrypsin-like peptidase (Vipera sp.)S01.520-
kangshuanmei peptidaseS01.524-
pepK (Porphyromonas gingivalis)S01.527-
glutenin peptidase 3 (Eurygaster integricepts)S01.528-
PREDICTED: similar to mast cell protease 4-like 1 precursor (Rattus norvegicus)S01.929-
Mername-AA172 peptidaseS01.930-
kallikrein 1-related peptidase b4 (Mus musculus)S01.931Yes
kallikrein 1 precursor (Rattus norvegicus)S01.932-
brain-rescue-factor-1 (Homo sapiens)S01.933-
hCG2041108 proteinS01.934-
CLIPA8 (Anopheles gambiae) and similarS01.936-
polyserase homologue (Mus musculus) unit 2S01.937-
polyserase homologue (Mus musculus) unit 3 and similarS01.938-
mast cell proteinase-4 (Ovis aries) (possible frameshift at C-terminus so lacks catalytic Ser)S01.939-
polyserase-2 unit 2S01.940-
polyserase-2 unit 3S01.941-
kallikrein-related peptidase 9-like proteinS01.945-
Mername-AA201 peptidase homologueS01.951-
secreted trypsin-like serine peptidase homologueS01.957-
4930478A21RIK protein (Mus musculus)S01.958-
CLIP-domain prophenoloxidase activating factorS01.960-
putative protein similar to trypsin X3 (Bos taurus) and similarS01.967-
Mername-AA179 proteinS01.968-
polyserase-1A unit 3S01.969-
azurocidinS01.971Yes
haptoglobin-1S01.972-
haptoglobin-related proteinS01.974-
macrophage-stimulating proteinS01.975Yes
hepatocyte growth factorS01.976Yes
hepatocyte growth factor-like protein homologueS01.977-
HGF activator-like proteinS01.978-
protein ZS01.979-
fibroblast-derived mammary growth factorS01.982-
carboxypeptidase A complex component IIIS01.983Yes
trypsin-like protein (mouse-type)S01.984-
TESP1 proteinS01.985-
Prss37 proteinS01.989-
LOC615237 proteinS01.990-
4930519f16rik proteinS01.991-
plasma kallikrein-like protein 4S01.992-
testis-specific protein 50S01.993-
PRSS35 proteinS01.994-
1300015b06rik protein (Mus musculus) and similarS01.996-
PAMR1 g.p. (Homo sapiens)S01.998-
apolipoproteinS01.999-
CG17240 protein (Drosophila melanogaster)S01.A11-
CG30286, domain 1 (Drosophila melanogaster)S01.A12-
CG30286, domain 3 (Drosophila melanogaster)S01.A13-
CG11530 protein, domain 1 (Drosophila melanogaster)S01.A15-
CG11530 protein, domain 2 (Drosophila melanogaster)S01.A16-
CG8528 (Drosophila melanogaster)S01.A17-
CG31205 protein (Drosophila melanogaster)S01.A18-
CG33458 (Drosophila melanogaster)S01.A19-
CG33160 (Drosophila melanogaster)S01.A20-
CG32755 (Drosophila melanogaster)S01.A21-
CG31220 (Drosophila melanogaster)S01.A22-
CG34409 protein (Drosophila melanogaster)S01.A23-
CG31219-PB protein (Drosophila melanogaster)S01.A24-
CG2045 (Drosophila melanogaster)S01.A25-
CG31681 (Drosophila melanogaster)S01.A26-
CG33462-RA (Drosophila melanogaster)S01.A27-
CG4827-RA (Drosophila melanogaster)S01.A28-
seminase (Drosophila melanogaster)S01.A29-
CG30288 protein (Drosophila melanogaster)S01.A30-
CG11670 protein (Drosophila melanogaster)S01.A31-
CG34290 protein (Drosophila melanogaster)S01.A32-
serine peptidase 6 (Drosophila melanogaster)S01.A33-
CG11664 protein (Drosophila melanogaster)S01.A34-
CG14780 protein (Drosophila melanogaster)S01.A35-
CG8952 protein (Drosophila melanogaster)S01.A36-
CG8170 protein (Drosophila melanogaster)S01.A37-
CG12133 protein (Drosophila melanogaster)S01.A38-
CG11192 protein (Drosophila melanogaster)S01.A39-
CG11037 protein (Drosophila melanogaster)S01.A40-
CG10587 protein (Drosophila melanogaster)S01.A41-
CG12256 protein (Drosophila melanogaster)S01.A42-
CG11668 protein (Drosophila melanogaster)S01.A43-
CG9649 protein (Drosophila melanogaster)S01.A44-
CG30088 protein (Drosophila melanogaster)S01.A45-
CG30087 protein (Drosophila melanogaster)S01.A46-
CG30287 protein (Drosophila melanogaster)S01.A47-
CG14642 protein (Drosophila melanogaster)S01.A48-
CG33159 protein (Drosophila melanogaster)S01.A49-
CG18636 protein (Drosophila melanogaster)S01.A50-
CG2105 (Drosophila melanogaster)S01.A51-
Sp212 protein (Drosophila melanogaster)S01.A52-
CG7432 protein (Drosophila melanogaster)S01.A53-
CG32277 (Drosophila melanogaster)S01.A54-
Cg32271 protein (Drosophila melanogaster)S01.A55-
Cg30083 protein (Drosophila melanogaster)S01.A56-
CG18754 protein (Drosophila melanogaster)S01.A57-
CG13744 protein (Drosophila melanogaster)S01.A58-
CG13430 protein (Drosophila melanogaster)S01.A59-
CG11313 (Drosophila melanogaster)S01.A60-
CG9733 protein (Drosophila melanogaster)S01.A61-
CG7829 protein (Drosophila melanogaster)S01.A62-
CG4815 protein (Drosophila melanogaster)S01.A63-
CG5909 protein (Drosophila melanogaster)S01.A64-
CG10232 protein (Drosophila melanogaster)S01.A65-
CG16710 protein (Drosophila melanogaster)S01.A66-
CG14892 protein (Drosophila melanogaster)S01.A67-
CG8870 protein (Drosophila melanogaster)S01.A68-
CG10041 protein (Drosophila melanogaster)S01.A69-
CG17404 protein (Drosophila melanogaster)S01.A70-
CG12949 protein (Drosophila melanogaster)S01.A71-
CG1304 protein (Drosophila melanogaster)S01.A72-
CG6592 protein (Drosophila melanogaster)S01.A73-
CG16998 protein (Drosophila melanogaster)S01.A74-
CG6865 protein (Drosophila melanogaster)S01.A75-
CG3650 protein (Drosophila melanogaster)S01.A76-
CG6048 protein (Drosophila melanogaster)S01.A77-
CG6041 protein (Drosophila melanogaster)S01.A78-
CG9631 protein (Drosophila melanogaster)S01.A79-
CG4812 protein (Drosophila melanogaster)S01.A81-
CG18681 protein (Drosophila melanogaster)S01.A82-
trypsin beta (Drosophila melanogaster)S01.A83-
trypsin gamma (Drosophila melanogaster)S01.A84-
CG17571 protein (Drosophila melanogaster)S01.A85-
CG17239 (Drosophila melanogaster)S01.A86-
trypsin lambda (Drosophila melanogaster)S01.A87-
CG32523 protein (Drosophila melanogaster)S01.A88-
CG9676 protein (Drosophila melanogaster)S01.A89-
IP08381 protein (Drosophila melanogaster)S01.A90-
Try29F protein (Drosophila melanogaster)S01.A91-
CG17477 protein (Drosophila melanogaster)S01.A92-
CG5255 protein (Drosophila melanogaster)S01.A93-
CG5246 protein (Drosophila melanogaster)S01.A94-
CG4053 protein (Drosophila melanogaster)S01.A95-
CG17475 protein (Drosophila melanogaster)S01.A96-
CG5233 protein (Drosophila melanogaster)S01.A97-
LP12217p (Drosophila melanogaster)S01.B01-
RH35407p (Drosophila melanogaster)S01.B02-
jonah 25Bi, isoform A (Drosophila melanogaster)S01.B03-
CG6462 (Drosophila melanogaster)S01.B04-
jonah 65Aiv (Drosophila melanogaster)S01.B05-
jonah 65Aii (Drosophila melanogaster)S01.B06-
CG7542 protein (Drosophila melanogaster)S01.B07-
CG8579 protein (Drosophila melanogaster)S01.B08-
CG18030 protein (Drosophila melanogaster)S01.B09-
CG8869 protein (Drosophila melanogaster)S01.B10-
CG8871 protein (Drosophila melanogaster)S01.B11-
CG10477 protein (Drosophila melanogaster)S01.B12-
CG6457 protein (Drosophila melanogaster)S01.B13-
CG6483 protein (Drosophila melanogaster)S01.B14-
CG10475 protein (Drosophila melanogaster)S01.B15-
CG10472 protein (Drosophila melanogaster)S01.B16-
CG10469 protein (Drosophila melanogaster)S01.B17-
CG7118 protein (Drosophila melanogaster)S01.B18-
LP19363 protein (Drosophila melanogaster)S01.B19-
CG18179 protein (Drosophila melanogaster)S01.B20-
CG18180 protein (Drosophila melanogaster)S01.B21-
CG11529 protein (Drosophila melanogaster)S01.B22-
CG6298 protein (Drosophila melanogaster)S01.B23-
Ser99Dc protein (Drosophila melanogaster)S01.B24-
IP21814 protein (Drosophila melanogaster)S01.B25-
MIP05615 protein (Drosophila melanogaster)S01.B26-
spirit protein (Drosophila melanogaster)S01.B27-
CG4927 protein (Drosophila melanogaster)S01.B28-
CG11842 protein (Drosophila melanogaster)S01.B29-
CG3700 protein (Drosophila melanogaster)S01.B30-
melanization peptidase-1, isoform A (Drosophila melanogaster)S01.B31-
CG32260 protein (Drosophila melanogaster)S01.B32-
CG1299 protein (Drosophila melanogaster)S01.B33-
CG8213 protein, isoform C (Drosophila melanogaster)S01.B34-
CG34350 protein (Drosophila melanogaster)S01.B35-
CG8172 protein, isoform A (Drosophila melanogaster)S01.B36-
CG9294 protein (Drosophila melanogaster)S01.B37-
CG18735 protein (Drosophila melanogaster)S01.B38-
CG4613 protein (Drosophila melanogaster)S01.B39-
CG3355 protein (Drosophila melanogaster)S01.B40-
CG4914 protein (Drosophila melanogaster)S01.B41-
CG4386 protein (Drosophila melanogaster)S01.B42-
CG11836 protein (Drosophila melanogaster)S01.B43-
CG16821 protein (Drosophila melanogaster)S01.B44-
Hayan peptidase (Drosophila melanogaster)S01.B45-
CG32808 protein (Drosophila melanogaster)S01.B47-
CG16749 protein (Drosophila melanogaster)S01.B48-
CG12951 protein (Drosophila melanogaster)S01.B49-
CG8299 protein (Drosophila melanogaster)S01.B50-
CG3916 protein (Drosophila melanogaster)S01.B51-
IP05987 protein (Drosophila melanogaster)S01.B52-
IP21143 protein (Drosophila melanogaster)S01.B53-
CG30289 protein (Drosophila melanogaster)S01.B54-
Cg30090 protein (Drosophila melanogaster)S01.B55-
Cg30091 protein (Drosophila melanogaster)S01.B56-
Sd12357 protein (Drosophila melanogaster)S01.B57-
CG10764 protein (Drosophila melanogaster)S01.B58-
CG3487 protein (Drosophila melanogaster)S01.B59-
MIP16537 protein (Drosophila melanogaster)S01.B60-
IP10861 protein (Drosophila melanogaster)S01.B61-
CG30375 protein (Drosophila melanogaster)S01.B62-
CG14760 protein (Drosophila melanogaster)S01.B63-
CG16996 protein (Drosophila melanogaster)S01.B64-
CG7142 protein (Drosophila melanogaster)S01.B65-
IP09733 protein (Drosophila melanogaster)S01.B66-
CG11912 protein (Drosophila melanogaster)S01.B67-
CG11911 protein (Drosophila melanogaster)S01.B68-
SVH-1 peptidase (Caenorhabditis elegans)S01.B69-
try-3 g.p. (Caenorhabditis elegans)S01.B70-
f25e5.7 g.p. (Caenorhabditis elegans)S01.B71-
try-6 g.p. (Caenorhabditis elegans)S01.B72-
try-1 g.p. (Caenorhabditis elegans)S01.B73-
EG:9D2.4 protein (Drosophila melanogaster)S01.B75-
CG1773 g.p. (Drosophila melanogaster)S01.B76-
CG10663-PC, isoform C (Drosophila melanogaster)S01.B77-
CG34458-PA (Drosophila melanogaster)S01.B78-
CG31954 g.p. (Drosophila melanogaster)S01.B79-
PF1905 g.p. (Pyrococcus furiosus)S01.B82-
try-4 g.p. (Caenorhabditis elegans)S01.B83-
try-7 g.p. (Caenorhabditis elegans)S01.B84-
Mername-AA289 putative peptidase (Drosophila melanogaster)S01.B85-
CG18125 g.p. (Drosophila melanogaster)S01.B86-
Tryp_SPc g.p. (Brachydanio rerio)S01.B88-
BX936298.1 g.p. (Brachydanio rerio)S01.B89-
si:dkey-78l4.1 g.p. (Brachydanio rerio)S01.B90-
LOC563828 g.p. (Brachydanio rerio)S01.B91-
LOC100151458 g.p. (Brachydanio rerio)S01.B92-
kallikrein mGK2 pseudogene (Mus musculus)S01.P01-
mGK-14 pseudogene (Mus musculus)S01.P02-
mGK-15 pseudogene (Mus musculus)S01.P04-
trypsin XI pseudogene (Mus musculus)S01.P05-
mGK-12 pseudogene (Mus musculus)S01.P06-
MCP-Y1 serine peptidase pseudogene (Mus musculus)S01.P07-
psi-KLK1 pseudogene (Homo sapiens)S01.P08-
tryptase pseudogene IS01.P09-
tryptase pseudogene IIS01.P10-
tryptase pseudogene IIIS01.P11-
LOC641199 pseudogene (Mus musculus)S01.P12-
mGK-7 pseudogene (Mus musculus)S01.P13-
mGK-18 pseudogene (Mus musculus)S01.P14-
mGK-19 pseudogene (Mus musculus)S01.P15-
mGK-23 pseudogene (Mus musculus)S01.P16-
mGK-28 pseudogene (Mus musculus)S01.P17-
mGK-25 pseudogene (Mus musculus)S01.P18-
subfamily S1A non-peptidase homologuesnon-peptidase homologueYes
subfamily S1A unassigned peptidasesunassignedYes
Subfamily S1B
Name Peptidase subfamily S1B
Subfamily type peptidase S01.269 - glutamyl endopeptidase I (Staphylococcus aureus), MEROPS Accession MER0000264 (peptidase unit: 69-336)
Active site residues H119 D161 S237 
Statistics Sequences: 5799
Identifiers: 10
Identifiers with PDB entries: 7
Other databases CATH 2.40.10.20
HOMSTRAD sermam
HSSP 1agj
INTERPRO IPR000126
PFAM PF00089
PFAM PF13365
SCOP 50495
Downloadable files Sequence library [FastA format]
Sequence alignment [FastA format]
Phylogenetic tree [Newick format]
Peptidases and Homologues MEROPS ID Structure
glutamyl endopeptidase IS01.269Yes
exfoliatin AS01.270Yes
SplB peptidase (Staphylococcus aureus)S01.282Yes
SplC peptidase (Staphylococcus aureus)S01.283Yes
SprE glutamyl peptidaseS01.423-
glutamyl peptidase BIS01.443Yes
exfoliatin BS01.445-
EhxC peptidase (Staphylococcus-type)S01.450-
SplA peptidase (Staphylococcus aureus)S01.503Yes
ESP peptidase (Staphylococcus-type)S01.522-
SplD peptidase (Staphylococcus aureus)S01.526-
subfamily S1B non-peptidase homologuesnon-peptidase homologue-
subfamily S1B unassigned peptidasesunassignedYes
Subfamily S1C
Name Peptidase subfamily S1C
Subfamily type peptidase S01.273 - DegP peptidase (Escherichia coli), MEROPS Accession MER0000266 (peptidase unit: 114-269)
Active site residues H131 D161 S236 
Statistics Sequences: 9458
Identifiers: 44
Identifiers with PDB entries: 6
Other databases HOMSTRAD hs1ky9a
HSSP 1ky9
INTERPRO IPR001940
PANTHER PTHR22939
PFAM PF00089
PFAM PF13365
SCOP 50495
Downloadable files Sequence library [FastA format]
Sequence alignment [FastA format]
Phylogenetic tree [Newick format]
Peptidases and Homologues MEROPS ID Structure
cercarial elastase (Schistosoma sp.)S01.144-
DegP peptidaseS01.273Yes
DegQ peptidaseS01.274-
DegS peptidaseS01.275Yes
HtrA1 peptidase (Homo sapiens-type)S01.277-
HtrA2 peptidaseS01.278Yes
Deg2 chloroplast peptidaseS01.279Yes
HtrA3 peptidaseS01.284-
HtrA4 peptidaseS01.285-
Tysnd1 peptidaseS01.286-
Mername-AA207 peptidaseS01.329-
HtrA-like peptidase (Listeria-type)S01.364-
Mername-AA124 peptidaseS01.416-
Deg5 chloroplast peptidaseS01.441-
HtrA stress response protease (Brucella-type)S01.442-
HtrA peptidase (Streptococcus-type)S01.447-
MucD peptidaseS01.453-
bhpA peptidase (spirochaete)S01.454-
Deg1 chloroplast peptidaseS01.472Yes
Deg8 chloroplast peptidaseS01.474-
DmHtrA2-type peptidaseS01.476-
AlgW peptidaseS01.477-
HtrA peptidase (Chlamydia trachomatis-type)S01.480-
HtrA peptidase (Synechocystis-type)S01.482-
HtrA peptidase (Thermotoga maritima-type)S01.491Yes
venom serine peptidase (Hymenoptera)S01.492-
Htra2 peptidase (Mycobacterium-type)S01.494-
HtrA peptidase (Helicobacter-type)S01.500-
DEG15 peptidaseS01.501-
MarP peptidase (Mycobacterium tuberculosis)S01.513-
HtrA peptidase (Borrelia burgdorferi) and similarS01.525-
At3g16540 (Arabidopsis thaliana)S01.A01-
At1g65640 (Arabidopsis thaliana)S01.A02-
At3g16550 (Arabidopsis thaliana)S01.A03-
At5g36950 (Arabidopsis thaliana)S01.A04-
At5g40200 (Arabidopsis thaliana)S01.A05-
At5g40560 (Arabidopsis thaliana)S01.A06-
At1g65630 (Arabidopsis thaliana)S01.A07-
At5g27660 (Arabidopsis thaliana)S01.A08-
At1g51150 (Arabidopsis thaliana)S01.A09-
CG3589 protein (Drosophila melanogaster)S01.A80-
TRY-5 peptidase (Caenorhabditis elegans)S01.B74-
htrA (Bacillus subtilis-type)S01.B81-
dsp1 g.p. (Plasmodium falciparum)S01.B87-
subfamily S1C non-peptidase homologuesnon-peptidase homologue-
subfamily S1C unassigned peptidasesunassigned-
Subfamily S1D
Name Peptidase subfamily S1D
Subfamily type peptidase S01.280 - lysyl endopeptidase (bacteria) (Achromobacter lyticus), MEROPS Accession MER0000277 (peptidase unit: 226-447)
Active site residues H262 D318 S399 
Statistics Sequences: 533
Identifiers: 7
Identifiers with PDB entries: 3
Other databases CATH 2.40.10.10
HOMSTRAD serbact
HSSP 1arc
INTERPRO IPR001254
PFAM PF00089
PFAM PF13365
SCOP 50495
Downloadable files Sequence library [FastA format]
Sequence alignment [FastA format]
Phylogenetic tree [Newick format]
Peptidases and Homologues MEROPS ID Structure
glutamyl peptidase BLS01.271-
glutamyl peptidase BSS01.272-
lysyl endopeptidase (bacteria)S01.280Yes
umbilical vein peptidaseS01.309-
Nma111 peptidaseS01.434-
alkaline endopeptidase (Nesterenkonia sp.)S01.499Yes
BSU6633_13792 g.p. (Bacillus subtilis)S01.B80-
subfamily S1D non-peptidase homologuesnon-peptidase homologue-
subfamily S1D unassigned peptidasesunassignedYes
Subfamily S1E
Name Peptidase subfamily S1E
Subfamily type peptidase S01.261 - streptogrisin A (Streptomyces griseus), MEROPS Accession MER0000251 (peptidase unit: 116-297)
Active site residues H149 D171 S253 
Statistics Sequences: 1101
Identifiers: 13
Identifiers with PDB entries: 7
Other databases CATH 2.40.10.10
HOMSTRAD serbact
HSSP 9lpr
INTERPRO IPR001316
PFAM PF00089
SCOP 50495
Downloadable files Sequence library [FastA format]
Sequence alignment [FastA format]
Phylogenetic tree [Newick format]
Peptidases and Homologues MEROPS ID Structure
streptogrisin AS01.261Yes
streptogrisin BS01.262Yes
SAM-P20 peptidaseS01.263-
streptogrisin CS01.265-
streptogrisin DS01.266-
streptogrisin ES01.267Yes
alpha-lytic endopeptidaseS01.268Yes
yeast-lytic peptidaseS01.276-
arginyl peptidaseS01.281-
NAPase (Nocardiopsis alba)S01.393Yes
CHY1 peptidase (Metarhizium anisopliae)S01.412-
SFase-2 endopeptidaseS01.431Yes
cellulomonadinS01.470Yes
subfamily S1E non-peptidase homologuesnon-peptidase homologue-
subfamily S1E unassigned peptidasesunassigned-
Subfamily S1F
Name Peptidase subfamily S1F
Subfamily type peptidase S01.109 - astrovirus serine peptidase (Mamastrovirus 1), MEROPS Accession MER0010934 (peptidase unit: 448-579)
Active site residues H462 D490 S552 
Statistics Sequences: 63
Identifiers: 1
Identifiers with PDB entries: 1
Other databases INTERPRO IPR009003
PFAM PF13365
Downloadable files Sequence library [FastA format]
Sequence alignment [FastA format]
Phylogenetic tree [Newick format]
Peptidases and Homologues MEROPS ID Structure
astrovirus serine peptidaseS01.109Yes
subfamily S1F unassigned peptidasesunassigned-
Peptidases not assigned to subfamily
Peptidases and Homologues MEROPS ID Structure
family S1 non-peptidase homologuesnon-peptidase homologue-
family S1 unassigned peptidasesunassigned-