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Updated: Jun 12, 2025

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
Serine 85 functions as a catalytic acid in the reprotonation process during EvAS-catalyzed astellifadiene
Weiyan Zhang1, Kaitong Peng1, Keying Lan1
1State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. liuxueting@ecust.edu.cn.
Abstract:
The deprotonation-reprotonation sequence introduces additional cyclization branches in terpene biosynthesis. However, the underlying mechanism remains poorly understood. In this study, we employed a combined approach of molecular dynamics (MD) simulations and site-directed mutagenesis on astellifadiene synthase EvAS from Emericella variecolor to investigate the role of a protonated S85 residue. This residue acts as a catalytic acid, previously unreported, that facilitates the reprotonation step in astellifadiene biosynthesis. Mutating S85 led to the production of a new tricyclic sesterterpene.
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