2H4C

Structure of Daboiatoxin (heterodimeric PLA2 venom)

2H4C の概要

• エントリーDOI: 10.2210/pdb2h4c/pdb
• 分子名称: Phospholipase A2-III, Phospholipase A2-II (3 entities in total)
• 機能のキーワード: phospholipase a2, non-inhibitor acidic pla2, basic pla2, heterodimer, hydrolase
• 由来する生物種: Daboia russellii siamensis; 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 110696.86

構造登録者

Gopalan, G.,Thwin, M.M.,Gopalakrishnakone, P.,Swaminathan, K. (登録日: 2006-05-24, 公開日: 2007-05-29, 最終更新日: 2024-11-20)

主引用文献

Gopalan, G.,Thwin, M.M.,Gopalakrishnakone, P.,Swaminathan, K.
Structural and pharmacological comparison of daboiatoxin from Daboia russelli siamensis with viperotoxin F and vipoxin from other vipers.
ACTA CRYSTALLOGR.,SECT.D, 63:722-729, 2007

PubMed Abstract: Russell's viper (Vipera russelli, also known as Daboia russelli) is one of the major causes of fatal snakebites. To date, five Daboia russelli subspecies have been recognized. Daboiatoxin (DbTx) is the main lethal phospholipase A(2) (PLA(2)) toxin in the venom of D. russelli siamensis (Myanmar viper) and has strong neurotoxic, myotoxic and cytotoxic activities. DbTx and its homologous neurotoxins viperotoxin F from D. russelli formosensis (Taiwan viper) and vipoxin from the Bulgarian sand viper V. ammodytes meridionalis consist of complexes between a nontoxic acidic PLA(2) protein and an enzymatically active basic PLA(2). DbTx and viperotoxin F are presynaptic toxins, while vipoxin is postsynaptic. The two chains of DbTx have been separated and their PLA(2) enzymatic activity has been measured using the secretory PLA(2) assay kit. The enzymatic activity of DbTx chain B is reduced by 30% of its original activity by chain A in a unimolar ratio, thus indicating that DbTx chain A acts as an inhibitor. The lethal activity of the two chains has also been studied in male albino mice and chain A is less lethal than chain B. The crystal structure of DbTx has also been determined and its structural details are compared with those of the two homologues. Furthermore, an attempt is made to correlate the sequence and structural determinants of these toxins with their enzymatic activities and their pharmacological effects.

PubMed: 17505111
DOI: 10.1107/S0907444907016204

実験手法

X-RAY DIFFRACTION (2.6 Å)