1M8T

Structure of an acidic Phospholipase A2 from the venom of Ophiophagus hannah at 2.1 resolution from a hemihedrally twinned crystal form

1M8T の概要

• エントリーDOI: 10.2210/pdb1m8t/pdb
• 分子名称: Phospholipase a2, CALCIUM ION, HEXANE-1,6-DIOL, ... (4 entities in total)
• 機能のキーワード: phospholipase a2 structure, twinned crystal, alpha, beta, hydrolase
• 由来する生物種: Ophiophagus hannah (king cobra)
• 細胞内の位置: Secreted (By similarity): Q9DF33
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 80625.76

構造登録者

Xu, S.,Gu, L.,Wang, Q.,Shu, Y.,Lin, Z. (登録日: 2002-07-26, 公開日: 2003-09-02, 最終更新日: 2024-10-30)

主引用文献

Xu, S.,Gu, L.,Wang, Q.,Shu, Y.,Song, S.,Lin, Z.
Structure of a king cobra phospholipase A2 determined from a hemihedrally twinned crystal.
Acta Crystallogr.,Sect.D, 59:1574-1581, 2003

PubMed Abstract: An acidic PLA(2) (OH APLA(2)-II) from the venom of Ophiophagus hannah (king cobra) shows greater phospholipase A(2) activity and weaker cardiotoxic and myotoxic activity than a homologous acidic PLA(2) from the same venom. The crystal of the enzyme belongs to space group P6(3). The crystals are invariably hemihedrally twinned, exhibiting perfect 622 Laue symmetry. The structure was determined by molecular replacement and refined using a hemihedral twinning program at 2.1 A resolution. The final model has reasonable stereochemistry and a crystallographic R factor of 19.5% (R(free) = 21.5%). The structure reveals the molecular arrangement and the mode of twinning. There are six independent molecules in the asymmetric unit. Owing to the presence of a non-crystallographic twofold parallel to the hemihedral twinning twofold, the molecular packing in the twinned crystal is extremely similar to that in an untwinned crystal for four of the molecules. This unique molecular arrangement may be related to the difficulty in recognizing the twinning. The structure was compared with the previously determined structure of a homologous acidic PLA(2) from the same source. The comparison shows structural changes that might be implicated in the increased catalytic activity and weakened toxicity.

PubMed: 12925787
DOI: 10.1107/S0907444903014598

実験手法

X-RAY DIFFRACTION (2.1 Å)