Crystallographic and Thermodynamic Evidence of Negative Coupling in the Flavin-Dependent Tryptophan Halogenases AbeH and BorH.

ABSTRACT: Flavin-dependent halogenases (FDHs) regioselectively halogenate aromatic substrates using halide ions, O₂, and reduced flavin (FADH₂) at physiological temperatures in aqueous solution, making them a green alternative to conventional synthetic methods for aryl halide preparation. To better understand mechanistic details that limit FDH catalytic efficiency and potentially hinder their application as in vitro biocatalysts, we investigated the halogenation activity, substrate scope, crystal structures, and ligand binding of the Trp-5-halogenase AbeH and the Trp-6-halogenase BorH. Partitioning of FAD and Trp into different subunits of BorH crystals and an inability to incorporate Trp into AbeH/FAD crystals suggested that binding of flavin and Trp are negatively coup

SUBMITTER: Ashaduzzaman M 

PROVIDER: S-EPMC11840605 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature