4EUH

Crystal structure of Clostridium acetobutulicum trans-2-enoyl-CoA reductase apo form

4EUH の概要

• エントリーDOI: 10.2210/pdb4euh/pdb
• 関連するPDBエントリー: 4EUE 4EUF 4FBG
• 分子名称: Putative reductase CA_C0462, SODIUM ION (3 entities in total)
• 機能のキーワード: ter, biofuel, synthetic biology, reductase, catalytic mechanism, substrate specificity, oxidoreductase
• 由来する生物種: Clostridium acetobutylicum
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 48289.87

構造登録者

Hu, K.,Zhao, M.,Zhang, T.,Yang, S.,Ding, J. (登録日: 2012-04-25, 公開日: 2012-11-28, 最終更新日: 2023-12-06)

主引用文献

Hu, K.,Zhao, M.,Zhang, T.,Zha, M.,Zhong, C.,Jiang, Y.,Ding, J.
Structures of trans-2-enoyl-CoA reductases from Clostridium acetobutylicum and Treponema denticola: insights into the substrate specificity and the catalytic mechanism
Biochem.J., 449:79-89, 2013

PubMed Abstract: TERs (trans-2-enoyl-CoA reductases; EC 1.3.1.44), which specifically catalyse the reduction of crotonyl-CoA to butyryl-CoA using NADH as cofactor, have recently been applied in the design of robust synthetic pathways to produce butan-1-ol as a biofuel. We report in the present paper the characterization of a CaTER (a TER homologue in Clostridium acetobutylicum), the structures of CaTER in apo form and in complexes with NADH and NAD+, and the structure of TdTER (Treponema denticola TER) in complex with NAD+. Structural and sequence comparisons show that CaTER and TdTER share approximately 45% overall sequence identity and high structural similarities with the FabV class enoyl-acyl carrier protein reductases in the bacterial fatty acid synthesis pathway, suggesting that both types of enzymes belong to the same family. CaTER and TdTER function as monomers and consist of a cofactor-binding domain and a substrate-binding domain with the catalytic active site located at the interface of the two domains. Structural analyses of CaTER together with mutagenesis and biochemical data indicate that the conserved Glu75 determines the cofactor specificity, and the conserved Tyr225, Tyr235 and Lys244 play critical roles in catalysis. Upon cofactor binding, the substrate-binding loop changes from an open conformation to a closed conformation, narrowing a hydrophobic channel to the catalytic site. A modelling study shows that the hydrophobic channel is optimal in both width and length for the binding of crotonyl-CoA. These results provide molecular bases for the high substrate specificity and the catalytic mechanism of TERs.

PubMed: 23050861
DOI: 10.1042/BJ20120871

実験手法

X-RAY DIFFRACTION (2.1 Å)