PA2TA_OXYSC
ID PA2TA_OXYSC Reviewed; 119 AA.
AC P00614;
DT 21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT 21-JUL-1986, sequence version 1.
DT 03-AUG-2022, entry version 117.
DE RecName: Full=Basic phospholipase A2 taipoxin alpha chain;
DE Short=svPLA2;
DE EC=3.1.1.4;
DE AltName: Full=Phosphatidylcholine 2-acylhydrolase;
OS Oxyuranus scutellatus scutellatus (Australian taipan) (Coastal taipan).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC Serpentes; Colubroidea; Elapidae; Acanthophiinae; Oxyuranus.
OX NCBI_TaxID=8667;
RN [1]
RP PROTEIN SEQUENCE.
RC TISSUE=Venom;
RX PubMed=7049694; DOI=10.1111/j.1432-1033.1982.tb06612.x;
RA Lind P., Eaker D.;
RT "Amino-acid sequence of the alpha-subunit of taipoxin, an extremely potent
RT presynaptic neurotoxin from the Australian snake taipan (Oxyuranus s.
RT scutellatus).";
RL Eur. J. Biochem. 124:441-447(1982).
RN [2]
RP PROTEIN SEQUENCE OF 1-4, FUNCTION, ENZYMATIC ACTIVITY, AND MASS
RP SPECTROMETRY.
RC TISSUE=Venom;
RX PubMed=22776098; DOI=10.1111/j.1742-4658.2012.08691.x;
RA Cendron L., Micetic I., Polverino de Laureto P., Paoli M.;
RT "Structural analysis of trimeric phospholipase A2 neurotoxin from the
RT Australian taipan snake venom.";
RL FEBS J. 279:3121-3135(2012).
RN [3]
RP FUNCTION, SUBUNIT, AND TOXIC DOSE.
RC TISSUE=Venom;
RX PubMed=976268; DOI=10.1111/j.1432-1033.1976.tb10833.x;
RA Fohlman J., Eaker D., Karlsoon E., Thesleff S.;
RT "Taipoxin, an extremely potent presynaptic neurotoxin from the venom of the
RT australian snake taipan (Oxyuranus s. scutellatus). Isolation,
RT characterization, quaternary structure and pharmacological properties.";
RL Eur. J. Biochem. 68:457-469(1976).
RN [4]
RP FUNCTION AS RCN2 BINDING PROTEIN.
RX PubMed=7722520; DOI=10.1046/j.1471-4159.1995.64052339.x;
RA Dodds D., Schlimgen A.K., Lu S.Y., Perin M.S.;
RT "Novel reticular calcium binding protein is purified on taipoxin columns.";
RL J. Neurochem. 64:2339-2344(1995).
RN [5]
RP FUNCTION AS PENTRAXIN BINDING PROTEIN.
RX PubMed=10748068; DOI=10.1074/jbc.m002254200;
RA Kirkpatrick L.L., Matzuk M.M., Dodds D.C., Perin M.S.;
RT "Biochemical interactions of the neuronal pentraxins. Neuronal pentraxin
RT (NP) receptor binds to taipoxin and taipoxin-associated calcium-binding
RT protein 49 via NP1 and NP2.";
RL J. Biol. Chem. 275:17786-17792(2000).
CC -!- FUNCTION: Heterotrimer: Snake venom phospholipase A2 (PLA2)
CC heterotrimer that acts as a potent presynaptic neurotoxin by blocking
CC synaptic transmission and synaptic vesicle recycling. May act by
CC binding in a calcium-dependent fashion to neurotonal pentraxin-1
CC (NPTX1) and neurotonal pentraxin-2 (NPTX2), but not to neuronal
CC pentraxin receptor (NPTXR). Also binds to taipoxin-associated calcium
CC binding protein 49 (RCN2), a protein localized in the lumen of
CC endoplasmic reticulum.
CC -!- FUNCTION: Monomer (alpha chain): Snake venom phospholipase A2 (PLA2)
CC alpha chain that possesses the same high enzymatic activity as the
CC heterotrimer. PLA2 catalyzes the calcium-dependent hydrolysis of the 2-
CC acyl groups in 3-sn-phosphoglycerides.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1-acyl-sn-
CC glycero-3-phosphocholine + a fatty acid + H(+); Xref=Rhea:RHEA:15801,
CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:28868,
CC ChEBI:CHEBI:57643, ChEBI:CHEBI:58168; EC=3.1.1.4;
CC Evidence={ECO:0000255|PROSITE-ProRule:PRU10035, ECO:0000255|PROSITE-
CC ProRule:PRU10036, ECO:0000269|PubMed:22776098};
CC -!- COFACTOR:
CC Name=Ca(2+); Xref=ChEBI:CHEBI:29108; Evidence={ECO:0000250};
CC Note=Binds 1 Ca(2+) ion. {ECO:0000250};
CC -!- SUBUNIT: Heterotrimer of alpha, beta, and gamma chains; non-covalently
CC linked. {ECO:0000269|PubMed:976268}.
CC -!- SUBCELLULAR LOCATION: Secreted.
CC -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC -!- MASS SPECTROMETRY: Mass=13987.9; Mass_error=0.8; Method=Electrospray;
CC Evidence={ECO:0000269|PubMed:22776098};
CC -!- TOXIC DOSE: Monomer (alpha chain): LD(50) is 0.3 mg/kg by intravenous
CC injection into mice. {ECO:0000269|PubMed:976268}.
CC -!- TOXIC DOSE: Heterotrimer: LD(50) is 2 ug/kg by intravenous injection
CC into mice. {ECO:0000269|PubMed:976268}.
CC -!- SIMILARITY: Belongs to the phospholipase A2 family. Group I subfamily.
CC D49 sub-subfamily. {ECO:0000305}.
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DR PIR; A00754; PSOXA.
DR AlphaFoldDB; P00614; -.
DR SMR; P00614; -.
DR PRIDE; P00614; -.
DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR GO; GO:0005509; F:calcium ion binding; IEA:InterPro.
DR GO; GO:0004623; F:phospholipase A2 activity; IEA:UniProtKB-EC.
DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR GO; GO:0050482; P:arachidonic acid secretion; IEA:InterPro.
DR GO; GO:0016042; P:lipid catabolic process; IEA:UniProtKB-KW.
DR GO; GO:0006644; P:phospholipid metabolic process; IEA:InterPro.
DR CDD; cd00125; PLA2c; 1.
DR Gene3D; 1.20.90.10; -; 1.
DR InterPro; IPR001211; PLipase_A2.
DR InterPro; IPR033112; PLipase_A2_Asp_AS.
DR InterPro; IPR016090; PLipase_A2_dom.
DR InterPro; IPR036444; PLipase_A2_dom_sf.
DR InterPro; IPR033113; PLipase_A2_His_AS.
DR PANTHER; PTHR11716; PTHR11716; 1.
DR Pfam; PF00068; Phospholip_A2_1; 1.
DR PRINTS; PR00389; PHPHLIPASEA2.
DR SMART; SM00085; PA2c; 1.
DR SUPFAM; SSF48619; SSF48619; 1.
DR PROSITE; PS00119; PA2_ASP; 1.
DR PROSITE; PS00118; PA2_HIS; 1.
PE 1: Evidence at protein level;
KW Calcium; Direct protein sequencing; Disulfide bond; Hydrolase;
KW Lipid degradation; Lipid metabolism; Metal-binding; Neurotoxin;
KW Presynaptic neurotoxin; Secreted; Toxin.
FT CHAIN 1..119
FT /note="Basic phospholipase A2 taipoxin alpha chain"
FT /id="PRO_0000161678"
FT ACT_SITE 48
FT /evidence="ECO:0000250"
FT ACT_SITE 93
FT /evidence="ECO:0000250"
FT BINDING 28
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250"
FT BINDING 30
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250"
FT BINDING 32
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250"
FT BINDING 49
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250"
FT DISULFID 11..72
FT /evidence="ECO:0000250"
FT DISULFID 27..118
FT /evidence="ECO:0000250"
FT DISULFID 29..45
FT /evidence="ECO:0000250"
FT DISULFID 44..99
FT /evidence="ECO:0000250"
FT DISULFID 51..92
FT /evidence="ECO:0000250"
FT DISULFID 61..85
FT /evidence="ECO:0000250"
FT DISULFID 79..90
FT /evidence="ECO:0000250"
SQ SEQUENCE 119 AA; 13829 MW; 7FAFD5DD61105C03 CRC64;
NLLQFGFMIR CANRRSRPVW HYMDYGCYCG KGGSGTPVDD LDRCCQVHDE CYGEAVRRFG
CAPYWTLYSW KCYGKAPTCN TKTRCQRFVC RCDAKAAECF ARSPYQNSNW NINTKARCR
