ID   SLB_BITAR               Reviewed;         125 AA.
AC   Q7LZK8;
DT   25-NOV-2008, integrated into UniProtKB/Swiss-Prot.
DT   15-DEC-2003, sequence version 1.
DT   25-MAY-2022, entry version 67.
DE   RecName: Full=Snaclec bitiscetin subunit beta;
OS   Bitis arietans (African puff adder).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC   Serpentes; Colubroidea; Viperidae; Viperinae; Bitis.
OX   NCBI_TaxID=8692;
RN   [1]
RP   PROTEIN SEQUENCE.
RC   TISSUE=Venom;
RA   Matsui T., Hamako J., Suzuki M., Hayashi N., Ito M., Makita K.,
RA   Fujimura Y., Ozeki Y., Titani K.;
RT   "Complete amino acid sequence of bitiscetin, a novel von Willebrand factor
RT   modulator protein purified from snake venom of Bitis arietans.";
RL   Biochem. Cell Biol. 1:271-284(1997).
RN   [2]
RP   PROTEIN SEQUENCE OF 1-20, AND FUNCTION.
RC   TISSUE=Venom;
RX   PubMed=8806626; DOI=10.1006/bbrc.1996.1345;
RA   Hamako J., Matsui T., Suzuki M., Ito M., Makita K., Fujimura Y., Ozeki Y.,
RA   Titani K.;
RT   "Purification and characterization of bitiscetin, a novel von Willebrand
RT   factor modulator protein from Bitis arietans snake venom.";
RL   Biochem. Biophys. Res. Commun. 226:273-279(1996).
RN   [3]
RP   FUNCTION.
RX   PubMed=12069583; DOI=10.1021/bi020004b;
RA   Matsui T., Hamako J., Matsushita T., Nakayama T., Fujimura Y., Titani K.;
RT   "Binding site on human von Willebrand factor of bitiscetin, a snake venom-
RT   derived platelet aggregation inducer.";
RL   Biochemistry 41:7939-7946(2002).
RN   [4]
RP   X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS), SUBUNIT, AND DISULFIDE BONDS.
RX   PubMed=11695907; DOI=10.1021/bi0114933;
RA   Hirotsu S., Mizuno H., Fukuda K., Qi M.C., Matsui T., Hamako J., Morita T.,
RA   Titani K.;
RT   "Crystal structure of bitiscetin, a von Willebrand factor-dependent
RT   platelet aggregation inducer.";
RL   Biochemistry 40:13592-13597(2001).
RN   [5]
RP   X-RAY CRYSTALLOGRAPHY (2.85 ANGSTROMS), SUBUNIT, AND DISULFIDE BONDS.
RX   PubMed=12851390; DOI=10.1074/jbc.m305566200;
RA   Maita N., Nishio K., Nishimoto E., Matsui T., Shikamoto Y., Morita T.,
RA   Sadler J.E., Mizuno H.;
RT   "Crystal structure of von Willebrand factor A1 domain complexed with snake
RT   venom, bitiscetin: insight into glycoprotein Ibalpha binding mechanism
RT   induced by snake venom proteins.";
RL   J. Biol. Chem. 278:37777-37781(2003).
CC   -!- FUNCTION: Snaclec that binds to von Willebrand factor (VWF) and induces
CC       its interaction with GPIbalpha (GP1BA) (via the vWF A1 domain),
CC       resulting in platelet aggregation. {ECO:0000269|PubMed:12069583,
CC       ECO:0000269|PubMed:8806626}.
CC   -!- SUBUNIT: Heterodimer of subunits alpha and beta; disulfide-linked.
CC       {ECO:0000269|PubMed:11695907, ECO:0000269|PubMed:12851390}.
CC   -!- SUBCELLULAR LOCATION: Secreted.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC   -!- SIMILARITY: Belongs to the snaclec family. {ECO:0000305}.
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DR   PIR; JC5059; JC5059.
DR   PDB; 1JWI; X-ray; 2.00 A; B=1-125.
DR   PDB; 1UEX; X-ray; 2.85 A; B=1-125.
DR   PDBsum; 1JWI; -.
DR   PDBsum; 1UEX; -.
DR   AlphaFoldDB; Q7LZK8; -.
DR   SMR; Q7LZK8; -.
DR   EvolutionaryTrace; Q7LZK8; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   Gene3D; 3.10.100.10; -; 1.
DR   InterPro; IPR001304; C-type_lectin-like.
DR   InterPro; IPR016186; C-type_lectin-like/link_sf.
DR   InterPro; IPR016187; CTDL_fold.
DR   Pfam; PF00059; Lectin_C; 1.
DR   SMART; SM00034; CLECT; 1.
DR   SUPFAM; SSF56436; SSF56436; 1.
DR   PROSITE; PS50041; C_TYPE_LECTIN_2; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Direct protein sequencing; Disulfide bond;
KW   Hemostasis impairing toxin; Platelet aggregation activating toxin;
KW   Secreted; Toxin.
FT   CHAIN           1..125
FT                   /note="Snaclec bitiscetin subunit beta"
FT                   /id="PRO_0000355241"
FT   DOMAIN          11..122
FT                   /note="C-type lectin"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00040"
FT   DISULFID        4..15
FT   DISULFID        32..121
FT   DISULFID        77
FT                   /note="Interchain (with C-79 in beta chain)"
FT   DISULFID        98..113
FT   CONFLICT        8
FT                   /note="W -> C (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   STRAND          9..11
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   STRAND          14..23
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   HELIX           25..35
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   STRAND          39..41
FT                   /evidence="ECO:0007829|PDB:1UEX"
FT   HELIX           47..59
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   STRAND          65..72
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   HELIX           74..76
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   STRAND          79..81
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   STRAND          97..102
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   TURN            103..105
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   STRAND          108..112
FT                   /evidence="ECO:0007829|PDB:1JWI"
FT   STRAND          117..124
FT                   /evidence="ECO:0007829|PDB:1JWI"
SQ   SEQUENCE   125 AA;  14798 MW;  0DDC68A8A3E5CD4E CRC64;
     DEGCLPDWSS YKGHCYKVFK VEKTWADAEK FCKELVNGGH LMSVNSREEG EFISKLALEK
     MRIVLVWIGL SHFWRICPLR WTDGARLDYR ALSDEPICFV AESFHNKWIQ WTCNRKKSFV
     CKYRV