title: Structure of a cardiotoxic phospholipase A(2) from Ophiophagus hannah with the "pancreatic loop".
abstract: The crystal structure of an acidic phospholipase A(2) from Ophiophagus hannah (king cobra) has been determined by molecular replacement at 2.6-A resolution to a crystallographic R factor of 20.5% (R(free)=23.3%) with reasonable stereochemistry. The venom enzyme contains an unusual "pancreatic loop." The conformation of the loop is well defined and different from those in pancreas PLA(2), showing its structural variability. This analysis provides the first structure of a PLA(2)-type cardiotoxin. The sites related to the cardiotoxic and myotoxic activities are explored and the oligomer observed in the crystalline state is described.
authors.affiliation: National Laboratory of Biomacromolecules, Institute of Biophysics, 100101, Beijing, China.
authors.forename: Hai-Long
authors.initials: HL
authors.lastname: Zhang
authors.forename: Su-Juan
authors.initials: SJ
authors.lastname: Xu
authors.forename: Qiu-Yan
authors.initials: QY
authors.lastname: Wang
authors.forename: Shi-Ying
authors.initials: SY
authors.lastname: Song
authors.forename: Yu-Yan
authors.initials: YY
authors.lastname: Shu
authors.forename: Zheng-Jiong
authors.initials: ZJ
authors.lastname: Lin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D004179:Cobra Cardiotoxin Proteins / Q000737:chemistry; D018360:Crystallography, X-Ray; D017815:Elapidae / Q000378:metabolism*; D004583:Electrons; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010741:Phospholipases A / Q000737:chemistry*; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
chemical_list: D004179:Cobra Cardiotoxin Proteins; D010741:Phospholipases A