Structure of a cardiotoxic phospholipase A(2) from Ophiophagus hannah with the "pancreatic loop".
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.
Zhang
Hai-Long
HL
National Laboratory of Biomacromolecules, Institute of Biophysics, 100101, Beijing, China.
Xu
Su-Juan
SJ
Wang
Qiu-Yan
QY
Song
Shi-Ying
SY
Shu
Yu-Yan
YY
Lin
Zheng-Jiong
ZJ
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
D004179:Cobra Cardiotoxin Proteins; D010741:Phospholipases A