5DHK

Nicotiana tabacum 5-epi-aristolochene synthase mutant W273E - alkylated

5DHK の概要

• エントリーDOI: 10.2210/pdb5dhk/pdb
• 関連するPDBエントリー: 5DHI
• 分子名称: 5-epi-aristolochene synthase, MAGNESIUM ION, FARNESYL, ... (4 entities in total)
• 機能のキーワード: sesquiterpene synthase, 5-epi-aristolochene synthase, farnesylation, active site alkylation, lyase
• 由来する生物種: Nicotiana tabacum (Common tobacco)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 61989.09

構造登録者

Noel, J.P.,Kersten, R.K. (登録日: 2015-08-31, 公開日: 2015-09-16, 最終更新日: 2023-09-27)

主引用文献

Kersten, R.D.,Diedrich, J.K.,Yates, J.R.,Noel, J.P.
Mechanism-Based Post-Translational Modification and Inactivation in Terpene Synthases.
Acs Chem.Biol., 10:2501-2511, 2015

PubMed Abstract: Terpenes are ubiquitous natural chemicals with diverse biological functions spanning all three domains of life. In specialized metabolism, the active sites of terpene synthases (TPSs) evolve in shape and reactivity to direct the biosynthesis of a myriad of chemotypes for organismal fitness. As most terpene biosynthesis mechanistically involves highly reactive carbocationic intermediates, the protein surfaces catalyzing these cascade reactions possess reactive regions possibly prone to premature carbocation capture and potentially enzyme inactivation. Here, we show using proteomic and X-ray crystallographic analyses that cationic intermediates undergo capture by conserved active site residues leading to inhibitory self-alkylation. Moreover, the level of cation-mediated inactivation increases with mutation of the active site, upon changes in the size and structure of isoprenoid diphosphate substrates, and alongside increases in reaction temperatures. TPSs that individually synthesize multiple products are less prone to self-alkylation then TPSs possessing relatively high product specificity. In total, the results presented suggest that mechanism-based alkylation represents an overlooked mechanistic pressure during the evolution of cation-derived terpene biosynthesis.

PubMed: 26378620
DOI: 10.1021/acschembio.5b00539

実験手法

X-RAY DIFFRACTION (2.43 Å)