Flavoenzymes: versatile catalysts in biosynthetic pathways.
Riboflavin-based coenzymes, tightly bound to enzymes catalyzing substrate oxidations and reductions, enable an enormous range of chemical transformations in biosynthetic pathways. Flavoenzymes catalyze substrate oxidations involving amine and alcohol oxidations and desaturations to olefins, the latter setting up Diels-Alder cyclizations in lovastatin and solanapyrone biosyntheses. Both C(4a) and N(5) of the flavin coenzymes are sites for covalent adduct formation. For example, the reactivity of dihydroflavins with molecular oxygen leads to flavin-4a-OOH adducts which then carry out a diverse range of oxygen transfers, including Baeyer-Villiger type ring expansions, olefin epoxidations, halogenations via transient HOCl generation, and an oxidative Favorskii rerrangement during enterocin assembly.
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Ave., Boston, MA 02115, USA. christopher_walsh@hms.harvard.edu
Christopher T
CT
Walsh
Timothy A
TA
Wencewicz
D053898:Biosynthetic Pathways; D002384:Catalysis; D005486:Flavin Mononucleotide / Q000378:metabolism; D006801:Humans; D015394:Molecular Structure; D010088:Oxidoreductases / Q000378:metabolism*; D012256:Riboflavin / Q000378:metabolism*
D005486:Flavin Mononucleotide; D010088:Oxidoreductases; D012256:Riboflavin