title: Crystal structure of an acidic phospholipase A2 from the venom of Agkistrodon halys pallas at 2.0 A resolution.
abstract: The crystal structure of acidic phospholipase A2 from the venom of Agkistrodon halys pallas has been determined by molecular replacement at 2.0 A resolution to a crystallographic R-factor of 0.157. The overall structure of the molecule is very similar to those of other phospholipase A2 species of known structure. The catalytic site, the hydrophobic channel and the N-terminal region show greatest structural conservation. The Ca(2+)-binding region has a conformation that resembles closely that of bovine PLA2 rather than Crotalus atrox PLA2. Compared with other PLA2 species, the conformation of the C-terminal ridge shows significant difference due to the insertion of two residues. A unique aromatic patch appears on one face of the molecules, surrounded by two acidic residues, the relevant features of this structure and their possible biological implications are discussed.
authors.affiliation: National Laboratory of Biomacromolecules, Academia Sinica, Beijing, China.
authors.forename: X Q
authors.initials: XQ
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Yang
authors.forename: L L
authors.initials: LL
authors.lastname: Gui
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Lin
authors.forename: Y C
authors.initials: YC
authors.lastname: Chen
authors.forename: Y C
authors.initials: YC
authors.lastname: Zhou
mesh_terms: D017836:Agkistrodon; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D003435:Crotalid Venoms; D017839:Crotalus; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008961:Models, Structural; D008969:Molecular Sequence Data; D010179:Pancreas / Q000201:enzymology; D010741:Phospholipases A / Q000737:chemistry* / Q000302:isolation & purification; D054467:Phospholipases A2; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid
chemical_list: C031442:Agkistrodon venoms; D003435:Crotalid Venoms; D010741:Phospholipases A; D054467:Phospholipases A2