Catalytic domain of Arabidopsis thaliana PI-PLC X domain-containing protein At5g67130 and its uncharacterized homologs
This subfamily corresponds to the catalytic domain present in Arabidopsis thaliana PI-PLC X domain-containing protein At5g67130 and its uncharacterized homologs. Members in this family show high sequence similarity to bacterial phosphatidylinositol-specific phospholipase C (PI-PLC, EC 4.6.1.13), which participates in Ca2+-independent PI metabolism, hydrolyzing the membrane lipid phosphatidylinositol (PI) to produce phosphorylated myo-inositol and diacylglycerol (DAG).
Comment:Both prokaryotic and eukaryotic PI-PLCs utilize a similar catalytic mechanism, a general base and acid catalysis involving two well conserved histidines. It consists of two steps, a phosphotransfer and a phosphodiesterase reaction.
Comment:Based on structure evidence of the catalytic site in Bacillus cereus phosphatidylinositol-specific phospholipase C.