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Introduction
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Reprogramming ThDP Enzymes for Z-Alkenes: Overriding Thermodynamic Preference via Noncovalent Controls.

Huangong Li^1,2, Tairan Yang¹, Yilong Zhao¹

¹State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.

Journal of the American Chemical Society

|June 29, 2026

Summary

This summary is machine-generated.

This study introduces a novel biocatalytic method for synthesizing Z-alkenes, overcoming the typical preference for E-isomers. The reprogrammed enzyme uses kinetic control for selective Z-alkene production, offering a sustainable alternative.

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Area of Science:

Biocatalysis
Organic Chemistry
Enzyme Engineering

Background:

Conventional alkene synthesis favors thermodynamically stable E-isomers, making direct Z-alkene synthesis challenging.
Thiamine diphosphate (ThDP)-dependent enzymes are crucial in C-C bond formation but not typically used for alkene synthesis.
Existing methods for Z-alkene synthesis often require complex strategies like substrate control or directing groups.

Purpose of the Study:

To reprogram a ThDP-dependent enzyme for the direct and selective synthesis of Z-α,β-unsaturated carboxylic acids.
To achieve kinetic control over alkene stereochemistry using enzyme active site engineering.
To develop a sustainable biocatalytic alternative to conventional Z-alkene synthesis methods.

Main Methods:

Reprogramming a ThDP-dependent enzyme via active site engineering.
Catalyzing a dehalogenative elimination reaction to override thermodynamic bias.
Utilizing noncovalent interactions within the enzyme's active site for stereochemical control.
Investigating a homoenolate-mediated pathway via a diverted Breslow intermediate.

Main Results:

Achieved direct and selective synthesis of Z-α,β-unsaturated carboxylic acids.
Demonstrated kinetic control for Z-alkene formation, overriding thermodynamic preference.
Engineered the enzyme for stereodivergent synthesis, enabling access to both E and Z isomers.
Established a biocatalytic platform for Z-alkene synthesis using noncovalent interactions.

Conclusions:

The reprogrammed enzyme provides a fundamentally distinct and sustainable approach to Z-alkene synthesis.
This work expands the catalytic capabilities of ThDP-dependent enzymes.
The biocatalytic platform addresses a critical need for efficient Z-alkene synthesis methodologies.