title: Structure of acidic phospholipase A2 for the venom of Agkistrodon halys blomhoffii at 2.8 A resolution.
abstract: The crystal structure of acidic phospholipase A2 from the venom of Agkistrodon halys blomhoffii has been determined by molecular replacement methods based on the known structure of Crotalus atrox PLA2, a same group II enzyme. The overall structures, except the calcium-binding regions, are very similar to each other. A calcium ion is pentagonally ligated to two carboxylate oxygen atoms of Asp-49 and each carbonyl oxygen atoms of Tyr-28, Gly-30 and Ala-31. A reason why the former enzyme functions as monomeric form, while the latter one does as dimer, could be presumed by the structural comparison of these calcium-binding regions. Although Gly-32 is usually participated as a ligand in the coordination with calcium ion in group I PLA2, it is characteristically replaced to Ala-31 in the present structure, and thus the coordination geometry of calcium ion is rather different from the usually observed one.
authors.affiliation: Osaka University of Pharmaceutical Sciences, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tomoo
authors.forename: H
authors.initials: H
authors.lastname: Ohishi
authors.forename: M
authors.initials: M
authors.lastname: Doi
authors.forename: T
authors.initials: T
authors.lastname: Ishida
authors.forename: M
authors.initials: M
authors.lastname: Inoue
authors.forename: K
authors.initials: K
authors.lastname: Ikeda
authors.forename: Y
authors.initials: Y
authors.lastname: Hata
authors.forename: Y
authors.initials: Y
authors.lastname: Samejima
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D003435:Crotalid Venoms / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010179:Pancreas / Q000201:enzymology; D010741:Phospholipases A / Q000737:chemistry* / Q000235:genetics; D054467:Phospholipases A2; D011487:Protein Conformation; D014961:X-Ray Diffraction
chemical_list: C031442:Agkistrodon venoms; D003435:Crotalid Venoms; D010741:Phospholipases A; D054467:Phospholipases A2