PA21_AGKPL
ID PA21_AGKPL Reviewed; 138 AA.
AC A0A411EZW9;
DT 02-JUN-2021, integrated into UniProtKB/Swiss-Prot.
DT 08-MAY-2019, sequence version 1.
DT 03-AUG-2022, entry version 10.
DE RecName: Full=Acidic phospholipase A2 AplTX-I {ECO:0000303|PubMed:28063838};
DE Short=svPLA2;
DE EC=3.1.1.4 {ECO:0000269|PubMed:28063838};
DE AltName: Full=Phosphatidylcholine 2-acylhydrolase;
DE Flags: Precursor;
OS Agkistrodon piscivorus leucostoma (Western cottonmouth) (Acontias
OS leucostoma).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC Serpentes; Colubroidea; Viperidae; Crotalinae; Agkistrodon.
OX NCBI_TaxID=459671;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RX PubMed=30691065; DOI=10.3390/toxins11020069;
RA Jia Y., Olvera P., Rangel F., Mendez B., Reddy S.;
RT "Rapid identification of phospholipase A(2) transcripts from snake
RT venoms.";
RL Toxins 11:69-69(2019).
RN [2]
RP PROTEIN SEQUENCE OF 17-98 AND 100-138, FUNCTION, CATALYTIC ACTIVITY,
RP BIOPHYSICOCHEMICAL PROPERTIES, COFACTOR, MASS SPECTROMETRY, SUBUNIT,
RP SUBCELLULAR LOCATION, AND 3D-STRUCTURE MODELING.
RC TISSUE=Venom;
RX PubMed=28063838; DOI=10.1016/j.toxicon.2017.01.002;
RA Resende L.M., Almeida J.R., Schezaro-Ramos R., Collaco R.C., Simioni L.R.,
RA Ramirez D., Gonzalez W., Soares A.M., Calderon L.A., Marangoni S.,
RA da Silva S.L.;
RT "Exploring and understanding the functional role, and biochemical and
RT structural characteristics of an acidic phospholipase A2, AplTx-I, purified
RT from Agkistrodon piscivorus leucostoma snake venom.";
RL Toxicon 127:22-36(2017).
RN [3]
RP ERRATUM OF PUBMED:28063838.
RX PubMed=28185673; DOI=10.1016/j.toxicon.2017.01.021;
RA Resende L.M., Almeida J.R., Ramos R.S., Collaco R.C., Simioni L.R.,
RA Ramirez D., Gonzalez W., Soares A.M., Calderon L.A., Marangoni S.,
RA da Silva S.L.;
RL Toxicon 128:61-61(2017).
CC -!- FUNCTION: Snake venom phospholipase A2 (PLA2) that triggers a high
CC neuromuscular toxicity in chick biventer cervicis preparations, but not
CC in mouse phrenic nerve-diaphragm (PND) preparations, suggesting a
CC selective neurotoxin activity towards birds (PubMed:28063838). Does not
CC induce myotoxic, coagulant, anticoagulant, edema, and antibacterial
CC activities (PubMed:28063838). PLA2 catalyzes the calcium-dependent
CC hydrolysis of the 2-acyl groups in 3-sn-phosphoglycerides
CC (PubMed:28063838). {ECO:0000269|PubMed:28063838}.
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:0000269|PubMed:28063838};
CC -!- COFACTOR:
CC Name=Ca(2+); Xref=ChEBI:CHEBI:29108;
CC Evidence={ECO:0000269|PubMed:28063838};
CC Note=Binds 1 Ca(2+) ion. {ECO:0000250|UniProtKB:P14418};
CC -!- ACTIVITY REGULATION: Inhibited by divalent cations different from
CC calcium ions (cadmium, magnesium, manganese, zinc), since they act as
CC competitive antagonists of this cofactor.
CC {ECO:0000269|PubMed:28063838}.
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=1.75 mM for 4-nitro-3-(octanoyloxy) benzoic acid (NOBA)
CC {ECO:0000269|PubMed:28063838};
CC Vmax=25.90 nM/min/mg enzyme {ECO:0000269|PubMed:28063838};
CC pH dependence:
CC Optimum pH is 8.0. {ECO:0000269|PubMed:28063838};
CC Temperature dependence:
CC Optimum temperature is 37 degrees Celsius.
CC {ECO:0000269|PubMed:28063838};
CC -!- SUBUNIT: Monomer. {ECO:0000269|PubMed:28063838}.
CC -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:28063838}.
CC -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC {ECO:0000305|PubMed:28063838}.
CC -!- MASS SPECTROMETRY: Mass=13885.79; Method=Electrospray;
CC Evidence={ECO:0000269|PubMed:28063838};
CC -!- SIMILARITY: Belongs to the phospholipase A2 family. Group II subfamily.
CC D49 sub-subfamily. {ECO:0000305}.
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DR EMBL; MK393887; QBA85139.1; -; mRNA.
DR AlphaFoldDB; A0A411EZW9; -.
DR SMR; A0A411EZW9; -.
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;
KW Hemostasis impairing toxin; Hydrolase; Lipid degradation; Lipid metabolism;
KW Metal-binding; Neurotoxin; Platelet aggregation inhibiting toxin;
KW Presynaptic neurotoxin; Secreted; Signal; Toxin.
FT SIGNAL 1..16
FT /evidence="ECO:0000269|PubMed:28063838"
FT CHAIN 17..138
FT /note="Acidic phospholipase A2 AplTX-I"
FT /evidence="ECO:0000305|PubMed:28063838"
FT /id="PRO_5018815989"
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:0000250|UniProtKB:P14418"
FT BINDING 45
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT BINDING 47
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT BINDING 64
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT DISULFID 42..131
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT DISULFID 44..60
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT DISULFID 59..111
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT DISULFID 65..138
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT DISULFID 66..104
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT DISULFID 73..97
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT DISULFID 91..102
FT /evidence="ECO:0000250|UniProtKB:P14418"
FT CONFLICT 31
FT /note="R -> Q (in Ref. 2; AA sequence)"
FT /evidence="ECO:0000305|PubMed:28063838"
FT CONFLICT 51
FT /note="R -> K (in Ref. 2; AA sequence)"
FT /evidence="ECO:0000305|PubMed:28063838"
FT CONFLICT 79
FT /note="S -> T (in Ref. 2; AA sequence)"
FT /evidence="ECO:0000305|PubMed:28063838"
FT CONFLICT 89
FT /note="V -> I (in Ref. 2; AA sequence)"
FT /evidence="ECO:0000305|PubMed:28063838"
SQ SEQUENCE 138 AA; 15685 MW; D903BBCD0481BE64 CRC64;
MRTLWIMAVL LLGVEGDLMQ FETLIMKIAK RSGMFWYSAY GCYCGWGGQG RPQDATDRCC
FVHDCCYGKV TGCDPKLDSY TYSVENGDVV CGGNDPCKKE ICECDRAAAI CFRDNKVTYD
NKYWRFPPQN CKEESEPC
