9NST

Bacterial Pictet-Spenglerase KslB in complex with product of L-Trp and a-ketoglutaric acid

これはPDB形式変換不可エントリーです。

9NST の概要

• エントリーDOI: 10.2210/pdb9nst/pdb
• 分子名称: Pictet-Spenglerase, (1~{S},3~{S})-1-(3-hydroxy-3-oxopropyl)-2,3,4,9-tetrahydropyrido[3,4-b]indole-1,3-dicarboxylic acid (2 entities in total)
• 機能のキーワード: pictet-spenglerase, biosynthetic protein
• 由来する生物種: Kitasatospora setae
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 212399.62

構造登録者

Kim, K.,Kim, W. (登録日: 2025-03-17, 公開日: 2025-04-23, 最終更新日: 2025-06-18)

主引用文献

Kim, W.,Zheng, Z.,Kim, K.,Lee, Y.H.,Liu, H.W.,Zhang, Y.J.
Structural and mechanistic insights into KslB, a bacterial Pictet-Spenglerase in kitasetaline biosynthesis.
Rsc Chem Biol, 6:933-941, 2025

PubMed Abstract: KslB is one of the few bacterial Pictet-Spenglerases recently identified in the biosynthesis of the β-carboline compound kitasetaline. While previous studies established that KslB catalyzes the condensation between l-tryptophan and α-ketoglutarate, the reaction mechanism, particularly its stereochemistry, remains poorly understood. This study presents five crystal structures of KslB, capturing key stages of reaction, shedding light on its catalytic dynamics. Among these, alternative binding poses of substrate and reaction product highlighted two significant features: (1) an additional pocket that accommodates l-tryptophan, and (2) two positively charged residues, Lys264 and Arg256, which form salt bridges with the product C1' and C5' carboxylate groups derived from α-ketoglutarate, ensuring a stereoselective process. These structural insights elucidate how KslB governs the stereochemistry of the cyclization process. Accordingly, we propose the configurations for the cyclized intermediate that align with the reaction's stereochemical outcome. Together, these findings offer valuable structural and mechanistic insights into KslB, paving the way for its potential engineering as a Pictet-Spengler biocatalyst.

PubMed: 40271149
DOI: 10.1039/d5cb00070j

実験手法

X-RAY DIFFRACTION (3.3 Å)