1CLP

CRYSTAL STRUCTURE OF A CALCIUM-INDEPENDENT PHOSPHOLIPASELIKE MYOTOXIC PROTEIN FROM BOTHROPS ASPER VENOM

1CLP の概要

• エントリーDOI: 10.2210/pdb1clp/pdb
• 分子名称: MYOTOXIN II (2 entities in total)
• 機能のキーワード: hydrolase
• 由来する生物種: Bothrops asper (terciopelo)
• 細胞内の位置: Secreted: P24605
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 27528.28

構造登録者

Arni, R.K.,Ward, R.J.,Gutierrez, J.M.,Tulinsky, A. (登録日: 1994-09-12, 公開日: 1994-11-30, 最終更新日: 2024-11-20)

主引用文献

Arni, R.K.,Ward, R.J.,Gutierrez, J.M.,Tulinsky, A.
Structure of a calcium-independent phospholipase-like myotoxic protein from Bothrops asper venom.
Acta Crystallogr.,Sect.D, 51:311-317, 1995

PubMed Abstract: Myotoxin II, a myotoxic calcium-independent phospholipase-like protein isolated from the venom of Bothrops asper, possesses no detectable phospholipase activity. The crystal structure has been determined and refined at 2.8 A to an R-factor of 16.5% (F > 3sigma) with excellent stereochemistry. Amino-acid differences between catalytically active phospholipases and myotoxin II in the Ca(2+)-binding region, specifically the substitutions Tyr28-->Asn, Gly32-->Leu and Asp49-->Lys, result in an altered local conformation. The key difference is that the epsilon-amino group of Lys49 fills the site normally occupied by the calcium ion in catalytically active phospholipases. In contrast to the homologous monomeric Lys49 variant from Agkistrodon piscivorus piscivorus, myotoxin II is present as a dimer both in solution and in the crystalline state. The two molecules in the asymmetric unit are related by a nearly perfect twofold axis, yet the dimer is radically different from the dimer formed by the phospholipase from Crotalus atrox. Whereas in C. atrox the dimer interface occludes the active sites, in myotoxin II they are exposed to solvent.

PubMed: 15299297
DOI: 10.1107/S0907444994011455

実験手法

X-RAY DIFFRACTION (2.8 Å)