2DSA

Ternary complex of BphK, a bacterial GST

2DSA の概要

• エントリーDOI: 10.2210/pdb2dsa/pdb
• 関連するPDBエントリー: 1A0F 1F2E 1PMT 2GDR
• 分子名称: Glutathione S-transferase, GLUTATHIONE, (2Z,4E)-2-HYDROXY-6-OXO-6-PHENYLHEXA-2,4-DIENOIC ACID, ... (4 entities in total)
• 機能のキーワード: glutathione s-transferase, transferase
• 由来する生物種: Burkholderia xenovorans
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 91691.01

構造登録者

Tocheva, E.I.,Murphy, M.E.P. (登録日: 2006-06-24, 公開日: 2006-08-22, 最終更新日: 2023-10-25)

主引用文献

Tocheva, E.I.,Fortin, P.D.,Eltis, L.D.,Murphy, M.E.P.
Structures of ternary complexes of BphK, a bacterial glutathione S-transferase that reductively dechlorinates polychlorinated biphenyl metabolites
J.Biol.Chem., 281:30933-30940, 2006

PubMed Abstract: Prokaryotic glutathione S-transferases are as diverse as their eukaryotic counterparts but are much less well characterized. BphK from Burkholderia xenovorans LB400 consumes two GSH molecules to reductively dehalogenate chlorinated 2-hydroxy-6-oxo-6-phenyl-2,4-dienoates (HOPDAs), inhibitory polychlorinated biphenyl metabolites. Crystallographic structures of two ternary complexes of BphK were solved to a resolution of 2.1A. In the BphK-GSH-HOPDA complex, GSH and HOPDA molecules occupy the G- and H-subsites, respectively. The thiol nucleophile of the GSH molecule is positioned for SN2 attack at carbon 3 of the bound HOPDA. The respective sulfur atoms of conserved Cys-10 and the bound GSH are within 3.0A, consistent with product release and the formation of a mixed disulfide intermediate. In the BphK-(GSH)2 complex, a GSH molecule occupies each of the two subsites. The three sulfur atoms of the two GSH molecules and Cys-10 are aligned suitably for a disulfide exchange reaction that would regenerate the resting enzyme and yield disulfide-linked GSH molecules. A second conserved residue, His-106, is adjacent to the thiols of Cys-10 and the GSH bound to the G-subsite and thus may stabilize a transition state in the disulfide exchange reaction. Overall, the structures support and elaborate a proposed dehalogenation mechanism for BphK and provide insight into the plasticity of the H-subsite.

PubMed: 16920719
DOI: 10.1074/jbc.M603125200

実験手法

X-RAY DIFFRACTION (2.1 Å)