PA2A1_ECHCA
ID PA2A1_ECHCA Reviewed; 136 AA.
AC Q7T3S7;
DT 03-OCT-2012, integrated into UniProtKB/Swiss-Prot.
DT 01-OCT-2003, sequence version 1.
DT 03-AUG-2022, entry version 91.
DE RecName: Full=Acidic phospholipase A2 EC-I;
DE Short=EC-I-PLA2;
DE Short=svPLA2;
DE EC=3.1.1.4;
DE AltName: Full=Phosphatidylcholine 2-acylhydrolase;
DE Flags: Precursor;
OS Echis carinatus (Saw-scaled viper).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC Serpentes; Colubroidea; Viperidae; Viperinae; Echis.
OX NCBI_TaxID=40353;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], PARTIAL PROTEIN SEQUENCE, X-RAY CRYSTALLOGRAPHY
RP (2.6 ANGSTROMS) OF 17-136 IN COMPLEX WITH CALCIUM ION, COFACTOR, SUBUNIT,
RP AND DISULFIDE BONDS.
RC TISSUE=Venom, and Venom gland;
RX PubMed=14684894; DOI=10.1107/s090744490302208x;
RA Jasti J., Paramasivam M., Srinivasan A., Singh T.P.;
RT "Structure of an acidic phospholipase A2 from Indian saw-scaled viper
RT (Echis carinatus) at 2.6 A resolution reveals a novel intermolecular
RT interaction.";
RL Acta Crystallogr. D 60:66-72(2004).
RN [2]
RP FUNCTION, AND BIOPHYSICOCHEMICAL PROPERTIES.
RC TISSUE=Venom;
RX PubMed=10519645; DOI=10.1016/s0041-0101(99)00104-x;
RA Kemparaju K., Krishnakanth T.P., Veerabasappa Gowda T.;
RT "Purification and characterization of a platelet aggregation inhibitor
RT acidic phospholipase A2 from Indian saw-scaled viper (Echis carinatus)
RT venom.";
RL Toxicon 37:1659-1671(1999).
CC -!- FUNCTION: Snake venom phospholipase A2 (PLA2) that inhibits human
CC platelet aggregation induced by ADP, collagen and epinephrin (possibly
CC by binding the platelet receptor alpha-IIb/beta-III) and induces mild
CC edema in the foot pads of mice. PLA2 catalyzes the calcium-dependent
CC hydrolysis of the 2-acyl groups in 3-sn-phosphoglycerides.
CC {ECO:0000269|PubMed:10519645}.
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};
CC -!- COFACTOR:
CC Name=Ca(2+); Xref=ChEBI:CHEBI:29108;
CC Evidence={ECO:0000305|PubMed:14684894};
CC Note=Binds 1 Ca(2+) ion. {ECO:0000305|PubMed:14684894};
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=1.66 mM for phospholipids {ECO:0000269|PubMed:10519645};
CC pH dependence:
CC Optimum pH is 7.5. {ECO:0000269|PubMed:10519645};
CC Temperature dependence:
CC Optimum temperature is 37 degrees Celsius.
CC {ECO:0000269|PubMed:10519645};
CC -!- SUBUNIT: Monomer. {ECO:0000269|PubMed:14684894}.
CC -!- SUBCELLULAR LOCATION: Secreted.
CC -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC -!- MISCELLANEOUS: Is non-lethal to mice and devoid of neurotoxicity,
CC myotoxicity, hemorrhage, anticoagulant activity and cytotoxicity.
CC {ECO:0000305|PubMed:10519645}.
CC -!- SIMILARITY: Belongs to the phospholipase A2 family. Group II subfamily.
CC D49 sub-subfamily. {ECO:0000305}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; AY268946; AAP41217.1; -; mRNA.
DR PDB; 1OZ6; X-ray; 2.60 A; A=17-136.
DR PDBsum; 1OZ6; -.
DR AlphaFoldDB; Q7T3S7; -.
DR SMR; Q7T3S7; -.
DR BindingDB; Q7T3S7; -.
DR ChEMBL; CHEMBL4195; -.
DR SABIO-RK; Q7T3S7; -.
DR EvolutionaryTrace; Q7T3S7; -.
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 3D-structure; Calcium; Direct protein sequencing; Disulfide bond;
KW Hemostasis impairing toxin; Hydrolase; Lipid degradation; Lipid metabolism;
KW Metal-binding; Platelet aggregation inhibiting toxin; Secreted; Signal;
KW Toxin.
FT SIGNAL 1..16
FT CHAIN 17..136
FT /note="Acidic phospholipase A2 EC-I"
FT /id="PRO_0000419211"
FT REGION 112..133
FT /note="May be responsible for inhibition of the platelet-
FT aggregation activity"
FT ACT_SITE 63
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT ACT_SITE 105
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT BINDING 43
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT BINDING 45
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT BINDING 47
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT BINDING 64
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT DISULFID 42..129
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT DISULFID 44..60
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT DISULFID 59..111
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT DISULFID 65..136
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT DISULFID 66..104
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT DISULFID 73..97
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT DISULFID 91..102
FT /evidence="ECO:0000269|PubMed:14684894,
FT ECO:0007744|PDB:1OZ6"
FT HELIX 18..29
FT /evidence="ECO:0007829|PDB:1OZ6"
FT HELIX 33..37
FT /evidence="ECO:0007829|PDB:1OZ6"
FT TURN 41..44
FT /evidence="ECO:0007829|PDB:1OZ6"
FT STRAND 45..47
FT /evidence="ECO:0007829|PDB:1OZ6"
FT HELIX 55..69
FT /evidence="ECO:0007829|PDB:1OZ6"
FT TURN 75..77
FT /evidence="ECO:0007829|PDB:1OZ6"
FT STRAND 82..85
FT /evidence="ECO:0007829|PDB:1OZ6"
FT STRAND 88..91
FT /evidence="ECO:0007829|PDB:1OZ6"
FT HELIX 96..113
FT /evidence="ECO:0007829|PDB:1OZ6"
FT HELIX 116..118
FT /evidence="ECO:0007829|PDB:1OZ6"
FT HELIX 121..124
FT /evidence="ECO:0007829|PDB:1OZ6"
SQ SEQUENCE 136 AA; 15523 MW; 39699DA1D01271BA CRC64;
MKTLWIVAVW LIAVEGNLYQ FGRMIWNRTG KLPILSYGSY GCYCGWGGQG PPKDATDRCC
LVHDCCYTRV GDCSPKMTLY SYRFENGDII CDNKDPCKRA VCECDREAAI CLGENVNTYD
KKYKSYEDCT EEVQEC
