8JG3

Biosynthetic thiolase from Clostridium kluyveri

8JG3 の概要

• エントリーDOI: 10.2210/pdb8jg3/pdb
• 分子名称: Acetyl-CoA C-acetyltransferase (2 entities in total)
• 機能のキーワード: biosynthetic thiolase, biosynthetic protein
• 由来する生物種: Clostridium kluyveri
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 85231.65

構造登録者

Kim, E.-J.,Seo, H.,Kim, K.-J. (登録日: 2023-05-19, 公開日: 2024-05-08, 最終更新日: 2025-11-19)

主引用文献

Jeon, B.S.,Kim, E.J.,Seo, H.,Kim, H.,Shin, S.,Schlaiss, C.,Angenent, L.T.,Kim, K.J.,Sang, B.I.
Molecular Chain Elongation Mechanism for n-Caproate Biosynthesis by Megasphaera Hexanoica.
Adv Sci, :e06069-e06069, 2025

PubMed Abstract: The microbial production of medium-chain carboxylates has attracted considerable interest owing to their potential applications in biofuels and specialty chemicals; however, the underlying biosynthetic mechanisms remain incompletely understood. The present study evaluates the medium-chain carboxylate-producing microbe Megaspahera hexanoica using genomic analysis, transcriptome analysis, and metabolic engineering. Additionally, the n-caproate synthesis pathway of M. hexanoica is characterized with fructose as an electron donor, and the substrate specificity of the respective proteins is evaluated by constructing an n-caproate biosynthetic pathway in Escherichia coli. Among all r-BOX or RBO genes, thl_1583, which encodes β-ketothiolase (MhTHL), is identified as the most critical enzyme for the carbon chain elongation mechanism in M. hexanoica. Therefore, MhTHL is compared with other well-studied β-ketothiolases (CkTHL from Clostridium kluyveri, ReBktB from Ralstonia eutropha (Cupriavidus necator), EcAtoB from E. coli, and CaTHL from C. acetobutylicum). MhTHL is found to exhibit the highest n-caproate production, as evidenced by the protein crystal structure of MhTHL. Structural comparisons with other thiolases show that MhTHL has a larger substrate-binding pocket than ReBktB. Thiolase mutants generated by site-directed mutagenesis reveal that two residues (Leu87 and Val351) are essential for determining the size of the substrate-binding pocket.

PubMed: 40932660
DOI: 10.1002/advs.202506069

実験手法

X-RAY DIFFRACTION (2 Å)