4xlo

Publication Abstract from PubMed

Flavoproteins catalyse a diversity of fundamental redox reactions and are one of the most studied enzyme families. As monooxygenases, they are universally thought to control oxygenation by means of a peroxyflavin species that transfers a single atom of molecular oxygen to an organic substrate. Here we report that the bacterial flavoenzyme EncM catalyses the peroxyflavin-independent oxygenation-dehydrogenation dual oxidation of a highly reactive poly(beta-carbonyl). The crystal structure of EncM with bound substrate mimics and isotope labelling studies reveal previously unknown flavin redox biochemistry. We show that EncM maintains an unexpected stable flavin-oxygenating species, proposed to be a flavin-N5-oxide, to promote substrate oxidation and trigger a rare Favorskii-type rearrangement that is central to the biosynthesis of the antibiotic enterocin. This work provides new insight into the fine-tuning of the flavin cofactor in offsetting the innate reactivity of a polyketide substrate to direct its efficient electrocyclization.

Flavin-mediated dual oxidation controls an enzymatic Favorskii-type rearrangement.,Teufel R, Miyanaga A, Michaudel Q, Stull F, Louie G, Noel JP, Baran PS, Palfey B, Moore BS Nature. 2013 Nov 28;503(7477):552-6. doi: 10.1038/nature12643. Epub 2013 Oct 27. PMID:24162851^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.