2Y53

Crystal structure of E257Q mutant of the box pathway encoded ALDH from Burkholderia xenovorans LB400

2Y53 の概要

• エントリーDOI: 10.2210/pdb2y53/pdb
• 関連するPDBエントリー: 2VRO 2Y51 2Y52 2Y5D
• 分子名称: ALDEHYDE DEHYDROGENASE (BOX PATHWAY), GLYCEROL, NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE, ... (4 entities in total)
• 機能のキーワード: oxidoreductase, nadp, nucleotide-binding
• 由来する生物種: BURKHOLDERIA XENOVORANS LB400
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 113529.23

構造登録者

Bains, J.,Leon, R.,Temke, K.G.,Boulanger, M.J. (登録日: 2011-01-11, 公開日: 2011-06-01, 最終更新日: 2024-05-08)

主引用文献

Bains, J.,Leon, R.,Temke, K.G.,Boulanger, M.J.
Elucidating the Reaction Mechanism of the Benzoate Oxidation Pathway Encoded Aldehyde Dehydrogenase from Burkholderia Xenovorans Lb400.
Protein Sci., 20:1048-, 2011

PubMed Abstract: Oxidation of cis-3,4-dehydroadipyl-CoA semialdehyde to cis-3,4-dehydroadipyl-CoA by the aldehyde dehydrogenase, ALDH(C) (EC.1.2.1.77), is an essential step in the metabolism of benzoate in Burkholderia xenovorans LB400. In a previous study, we established a structural blueprint for this novel group of ALDH enzymes. Here, we build significantly on this initial work and propose a detailed reaction mechanism for ALDH(C) based on comprehensive structural and functional investigations of active site residues. Kinetic analyses reveal essential roles for C296 as the nucleophile and E257 as the associated general base. Structural analyses of E257Q and C296A variants suggest a dynamic charge repulsion relationship between E257 and C296 that contributes to the inherent flexibility of E257 in the native enzyme, which is further regulated by E496 and E167. A proton relay network anchored by E496 and supported by E167 and K168 serves to reset E257 for the second catalytic step. We also propose that E167, which is unique to ALDH(C) and its homologs, serves a critical role in presenting the catalytic water to the newly reset E257 such that the enzyme can proceed with deacylation and product release. Collectively, the reaction mechanism proposed for ALDH(C) promotes a greater understanding of these novel ALDH enzymes, the ALDH super-family in general, and benzoate degradation in B. xenovorans LB400.

PubMed: 21495107
DOI: 10.1002/PRO.639

実験手法

X-RAY DIFFRACTION (1.4 Å)