Flavin-dependent halogenases and their applications

Abstract:

Halides are important raw materials in agriculture, pharmaceutical industry, and chemical industry. They are mainly synthesized with chemical methods which, however, cause environmental pollution and have strick requirement for the reaction conditions. The key enzymes for the biosynthesis of natural halides are halogenases, including haloperoxidase (HPO), α-ketoglutarate dependent halogenase (KG-Hal), S-adenosylmethionine-dependent halogenase, and flavin-dependent halogenase (FDH). Among them, FDHs are the most promising halogenases owing to their wide distribution, substrate specificity, and halogenated regioselectivity. Therefore, we reviewed the structures, types, catalytic mechanisms, and applications of FDHs and summarized the use of gene analysis and gene screening to search for new FDHs. This review is expected to expand the knowledge of the types and catalytic mechanisms of FDHs, boost the research on FDHs and related enzyme engineering, and provide technical ideas for the synthesis of new halides.

Key words:halogenase;flavin-dependent halogenase;catalytic mechanism;halide;biosynthesis