6ir4

Publication Abstract from PubMed

In biotin biosynthesis, the conversion of pimeloyl intermediates to biotin is catalyzed by a universal set of four enzymes: BioF, BioA, BioD and BioB. We found that the gene homologous to bioA, the product of which is involved in the conversion of 8-amino-7-oxononanoate (AON) to 7,8-diaminononanoate (DAN), is missing in the genome of the cyanobacterium Synechocystis sp. PCC 6803. We provide structural and biochemical evidence showing that a novel dehydrogenase, BioU, is involved in biotin biosynthesis and functionally replaces BioA. This enzyme catalyzes three reactions: formation of covalent linkage with AON to yield a BioU-DAN conjugate at the epsilon-amino group of Lys124 of BioU using NAD(P)H, carboxylation of the conjugate to form BioU-DAN-carbamic acid, and release of DAN-carbamic acid using NAD(P)(+). In this biosynthetic pathway, BioU is a suicide enzyme that loses the Lys124 amino group after a single round of reaction.

A suicide enzyme catalyzes multiple reactions for biotin biosynthesis in cyanobacteria.,Sakaki K, Ohishi K, Shimizu T, Kobayashi I, Mori N, Matsuda K, Tomita T, Watanabe H, Tanaka K, Kuzuyama T, Nishiyama M Nat Chem Biol. 2020 Feb 10. pii: 10.1038/s41589-019-0461-9. doi:, 10.1038/s41589-019-0461-9. PMID:32042199^[1]

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