P59888 · IPTXI_PANIM
- ProteinPhospholipase A2 imperatoxin-1
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids167 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Phospholipase toxin, which may catalyze the calcium-dependent hydrolysis of the 2-acyl groups in 3-sn-phosphoglycerides. Inhibits both skeletal (RYR1) and cardiac (RYR2) ryanodine receptors (calcium release channels). Probably blocks ryanodine receptors by generating a lipid product.
Catalytic activity
- a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1-acyl-sn-glycero-3-phosphocholine + a fatty acid + H+
Cofactor
Note: Binds 1 Ca2+ ion.
Features
Showing features for binding site, active site.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Binding site | 38 | Ca2+ (UniProtKB | ChEBI) | |||
Binding site | 40 | Ca2+ (UniProtKB | ChEBI) | |||
Binding site | 42 | Ca2+ (UniProtKB | ChEBI) | |||
Active site | 64 | ||||
Binding site | 65 | Ca2+ (UniProtKB | ChEBI) | |||
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | extracellular region | |
Molecular Function | calcium channel regulator activity | |
Molecular Function | metal ion binding | |
Molecular Function | phospholipase A2 activity | |
Molecular Function | toxin activity | |
Biological Process | arachidonic acid secretion | |
Biological Process | lipid catabolic process | |
Biological Process | phospholipid metabolic process |
Keywords
- Molecular function
- Biological process
- Ligand
Names & Taxonomy
Protein names
- Recommended namePhospholipase A2 imperatoxin-1
- Alternative names
- Cleaved into 2 chains
Organism names
- Taxonomic lineageEukaryota > Metazoa > Ecdysozoa > Arthropoda > Chelicerata > Arachnida > Scorpiones > Iurida > Scorpionoidea > Scorpionidae > Pandininae > Pandinus
Accessions
- Primary accessionP59888
Subcellular Location
Phenotypes & Variants
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Mutagenesis | 144 | Does not affect the binding of ryanodine to cardiac ryanodine receptor. | |||
PTM/Processing
Features
Showing features for propeptide, signal, chain, disulfide bond, glycosylation.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Propeptide | PRO_0000022988 | ?-31 | |||
Signal | 1-? | ||||
Chain | PRO_0000022989 | 32-135 | Imperatoxin-1 large subunit | ||
Disulfide bond | 39↔61 | ||||
Disulfide bond | 60↔99 | ||||
Disulfide bond | 67↔92 | ||||
Disulfide bond | 90↔127 | ||||
Glycosylation | 102 | N-linked (GlcNAc...) asparagine | |||
Disulfide bond | 132↔144 | Interchain (between large and small subunits) | |||
Propeptide | PRO_0000022990 | 136-140 | |||
Chain | PRO_0000022991 | 141-167 | Imperatoxin-1 small subunit | ||
Keywords
- PTM
Expression
Tissue specificity
Expressed by the venom gland.
Interaction
Subunit
Heterodimer composed of a large subunit and a small subunit; disulfide-linked.
Structure
Family & Domains
Sequence similarities
Belongs to the phospholipase A2 family. Group III subfamily.
Keywords
- Domain
Family and domain databases
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length167
- Mass (Da)18,664
- Last updated2003-09-26 v1
- Checksum027420BFB033B18E
Keywords
- Technical term