ID   PA2H4_BOTMT             Reviewed;          51 AA.
AC   P0DUN8;
DT   02-JUN-2021, integrated into UniProtKB/Swiss-Prot.
DT   02-JUN-2021, sequence version 1.
DT   25-MAY-2022, entry version 4.
DE   RecName: Full=Basic phospholipase A2 homolog BmatTX-IV {ECO:0000303|PubMed:31340737};
DE            Short=svPLA2 homolog;
DE   AltName: Full=Lys49 PLA2-like;
DE   Flags: Fragment;
OS   Bothrops matogrossensis (Pitviper) (Bothrops neuwiedi matogrossensis).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC   Serpentes; Colubroidea; Viperidae; Crotalinae; Bothrops.
OX   NCBI_TaxID=1171125;
RN   [1]
RP   PROTEIN SEQUENCE, FUNCTION, AND SUBCELLULAR LOCATION.
RC   TISSUE=Venom;
RX   PubMed=31340737; DOI=10.2174/1568026619666190723154756;
RA   Alfonso J.J., Kayano A.M., Garay A.F.G., Simoes-Silva R., Sobrinho J.C.,
RA   Vourliotis S., Soares A.M., Calderon L.A., Gomez M.C.V.;
RT   "Isolation, Biochemical Characterization and Antiparasitic Activity of
RT   BmatTX-IV, A Basic Lys49-Phospholipase A2 from the Venom of Bothrops
RT   mattogrossensis from Paraguay.";
RL   Curr. Top. Med. Chem. 19:2041-2048(2019).
CC   -!- FUNCTION: Snake venom phospholipase A2 homolog that lacks enzymatic
CC       activity (PubMed:31340737). Shows cytotoxic activity (IC(50)=81.2
CC       ug/mL) against murine fibroblasts (PubMed:31340737). Shows high
CC       myotoxic activity, neutrophile activation, slight cytotoxicity against
CC       tumor cell lines, and slight antiparasitic activity against
CC       promastigote forms of Leishmania amazonensis (By similarity). A model
CC       of myotoxic mechanism has been proposed: an apo Lys49-PLA2 is activated
CC       by the entrance of a hydrophobic molecule (e.g. fatty acid) at the
CC       hydrophobic channel of the protein leading to a reorientation of a
CC       monomer (By similarity). This reorientation causes a transition between
CC       'inactive' to 'active' states, causing alignment of C-terminal and
CC       membrane-docking sites (MDoS) side-by-side and putting the membrane-
CC       disruption sites (MDiS) in the same plane, exposed to solvent and in a
CC       symmetric position for both monomers (By similarity). The MDoS region
CC       stabilizes the toxin on membrane by the interaction of charged residues
CC       with phospholipid head groups (By similarity). Subsequently, the MDiS
CC       region destabilizes the membrane with penetration of hydrophobic
CC       residues (By similarity). This insertion causes a disorganization of
CC       the membrane, allowing an uncontrolled influx of ions (i.e. calcium and
CC       sodium), and eventually triggering irreversible intracellular
CC       alterations and cell death (By similarity).
CC       {ECO:0000250|UniProtKB:I6L8L6, ECO:0000250|UniProtKB:P0DMJ9,
CC       ECO:0000269|PubMed:31340737}.
CC   -!- SUBUNIT: Monomer. {ECO:0000250|UniProtKB:P0DMJ9}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:31340737}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC       {ECO:0000305|PubMed:31340737}.
CC   -!- SIMILARITY: Belongs to the phospholipase A2 family. Group II subfamily.
CC       K49 sub-subfamily. {ECO:0000305}.
CC   -!- CAUTION: Does not bind calcium as one of the calcium-binding sites is
CC       lost (Asp->Lys in position 48, which corresponds to 'Lys-49' in the
CC       current nomenclature). {ECO:0000305}.
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DR   AlphaFoldDB; P0DUN8; -.
DR   SMR; P0DUN8; -.
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:InterPro.
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:InterPro.
DR   GO; GO:0006644; P:phospholipid metabolic process; IEA:InterPro.
DR   Gene3D; 1.20.90.10; -; 1.
DR   InterPro; IPR001211; PLipase_A2.
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.
PE   1: Evidence at protein level;
KW   Direct protein sequencing; Disulfide bond; Myotoxin; Secreted; Toxin.
FT   CHAIN           1..>51
FT                   /note="Basic phospholipase A2 homolog BmatTX-IV"
FT                   /evidence="ECO:0000269|PubMed:31340737"
FT                   /id="PRO_0000452899"
FT   DISULFID        26..?
FT                   /evidence="ECO:0000250|UniProtKB:Q90249"
FT   DISULFID        28..44
FT                   /evidence="ECO:0000250|UniProtKB:Q90249"
FT   DISULFID        43..?
FT                   /evidence="ECO:0000250|UniProtKB:Q90249"
FT   DISULFID        49..?
FT                   /evidence="ECO:0000250|UniProtKB:Q90249"
FT   DISULFID        50..?
FT                   /evidence="ECO:0000250|UniProtKB:Q90249"
FT   NON_TER         51
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   51 AA;  5531 MW;  02301FDC8FD79D48 CRC64;
     SLVELGKMIL QETGKNPVTS YGAYGCNCGV LGRGKPKDAT DRCCYVHKCC Y