title: Specificity of two types of phospholipase A2 inhibitors from the plasma of venomous snakes.
abstract: Specificity of two different types of phospholipase A2 (PLA2) inhibitory proteins from the blood plasma of venomous snakes was investigated. Two Crotalidae inhibitors, having a carbohydrate recognition domain (CRD) in their sequences, inhibited specifically the group-II acidic PLA2s of their own snake venom. On the other hand, Elapidae inhibitor, having two tandem patterns of cysteine residues found in proteins of the Ly-6 superfamily, inhibited not only the group-I PLA2 from its own snake venom but also the group-I, -II, and -III PLA2s from other snake venom. Amino acid sequences of PLA2s that were specifically inhibited by the inhibitors were compared with those of the other PLA2s. A unique aromatic patch structure appeared on the group-II acidic PLA2s was suggested to be involved in the binding to the Crotalidae inhibitors; and residues located in or close to the Ca2+ binding loop of PLA2, in the binding to the Elapidae inhibitor.
authors.affiliation: Department of Biochemistry, Osaka University of Pharmaceutical Sciences, Japan. inoue@oysun01.oups.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Inoue
authors.forename: A
authors.initials: A
authors.lastname: Shimada
authors.forename: N
authors.initials: N
authors.lastname: Ohkura
authors.forename: K
authors.initials: K
authors.lastname: Ikeda
authors.forename: Y
authors.initials: Y
authors.lastname: Samejima
authors.forename: T
authors.initials: T
authors.lastname: Omori-Satoh
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
mesh_terms: D017836:Agkistrodon / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D017815:Elapidae / Q000378:metabolism*; D008969:Molecular Sequence Data; D010741:Phospholipases A / Q000037:antagonists & inhibitors*; D054467:Phospholipases A2; D017386:Sequence Homology, Amino Acid; D017841:Trimeresurus / Q000378:metabolism*
chemical_list: D010741:Phospholipases A; D054467:Phospholipases A2