ID   VSPCE_CERVI             Reviewed;          35 AA.
AC   P18692;
DT   01-NOV-1990, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1990, sequence version 1.
DT   03-AUG-2022, entry version 89.
DE   RecName: Full=Thrombin-like enzyme cerastobin;
DE            Short=SVTLE;
DE            EC=3.4.21.-;
DE   AltName: Full=Fibrinogen-clotting enzyme;
DE   AltName: Full=Snake venom serine protease;
DE            Short=SVSP;
DE   Flags: Fragment;
OS   Cerastes vipera (Sahara sand viper).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC   Serpentes; Colubroidea; Viperidae; Viperinae; Cerastes.
OX   NCBI_TaxID=8698;
RN   [1]
RP   PROTEIN SEQUENCE, FUNCTION, AND BIOPHYSICOCHEMICAL PROPERTIES.
RC   TISSUE=Venom;
RX   PubMed=2539861; DOI=10.1021/bi00427a051;
RA   Farid T.M., Tu A.T., El-Asmar M.F.;
RT   "Characterization of cerastobin, a thrombin-like enzyme from the venom of
RT   Cerastes vipera (Sahara sand viper).";
RL   Biochemistry 28:371-377(1989).
RN   [2]
RP   FUNCTION.
RX   PubMed=1963167; DOI=10.1159/000216141;
RA   Farid T.M., Tu A.T., El-Asmar M.F.;
RT   "Effect of cerastobin, a thrombinlike enzyme from Cerastes vipera (Egyptian
RT   sand snake) venom, on human platelets.";
RL   Haemostasis 20:296-304(1990).
CC   -!- FUNCTION: Thrombin-like snake venom serine protease, that cleaves both
CC       alpha-chain (FGA) and beta-chain (FGB) of fibrinogen. Partially
CC       degrades factor X (F10), and release bradykinin from kininogen (KNG).
CC       Potently induces platelet aggregation. Shows a proteolytic activity
CC       towards protein constituents of the platelets cytoskeleton. Hydrolyzes
CC       actin, actin-binding protein, and P235. Shows a preferential cleavage
CC       at Arg-|-Xaa bonds. {ECO:0000269|PubMed:1963167,
CC       ECO:0000269|PubMed:2539861}.
CC   -!- ACTIVITY REGULATION: Inhibited by diisopropylfluorophosphate (DFP).
CC   -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC       pH dependence:
CC         Optimum pH is 7.9. {ECO:0000269|PubMed:2539861};
CC       Temperature dependence:
CC         Optimum temperature is 45 degrees Celsius.
CC         {ECO:0000269|PubMed:2539861};
CC   -!- SUBUNIT: Monomer. {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Secreted.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC   -!- SIMILARITY: Belongs to the peptidase S1 family. Snake venom subfamily.
CC       {ECO:0000255|PROSITE-ProRule:PRU00274}.
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DR   PIR; A30104; A30104.
DR   AlphaFoldDB; P18692; -.
DR   SMR; P18692; -.
DR   MEROPS; S01.337; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0008236; F:serine-type peptidase activity; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   GO; GO:0006508; P:proteolysis; IEA:UniProtKB-KW.
PE   1: Evidence at protein level;
KW   Blood coagulation cascade activating toxin; Direct protein sequencing;
KW   Hemostasis impairing toxin; Hydrolase;
KW   Platelet aggregation activating toxin; Protease; Secreted; Serine protease;
KW   Toxin.
FT   CHAIN           1..>35
FT                   /note="Thrombin-like enzyme cerastobin"
FT                   /id="PRO_0000088737"
FT   DOMAIN          1..>35
FT                   /note="Peptidase S1"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00274"
FT   NON_TER         35
SQ   SEQUENCE   35 AA;  3982 MW;  11970C7D08EF8057 CRC64;
     VIGGAKCNIN EHRSIVLLYS SRLFGHTLIN KEWVL