Comparison of the crystal structures of threeMicropechis ikahekaphos-pholipase A2 isoenzymes (MiPLA2, MiPLA3 and MiPLA4, which exhibit different levels of pharmacological effects) shows that their C-terminus (residues 110–124) is the most variable. M-Type receptor binding affinity of the isoenzymes has also been investigated and MiPLA4 binds to the rabbit M-type receptor with high affinity. Examination of surface charges of the isoenzymes reveals a trend of increase in positive charges with potency
