6ir4

Structural highlights

Function

BIOU_SYNY3 A 'suicide' enzyme that participates in biotin synthesis. Catalyzes the formation of (S)-8-amino-7-oxononanoate (DAN-carbamic acid) from (7R,8S)-8-amino-7-(carboxyamino)nonanoate (DAN), a function equivalent to the cannonical BioA reaction and the first half-reaction of BioD. The cellular requirement for biotin is thought be low enough that this single turnover enzyme supplies a sufficient amount of the cofactor. Overall it catalyzes three reactions: formation of a covalent linkage with 8-amino-7-oxononanoate 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)+ (By similarity) (PubMed:32042199). A coupled Synechocystis BioU/BioD assay produces dethiobiotin from DAN. Complements a bioA deletion in E.coli but not a bioD1 deletion (PubMed:32042199).[HAMAP-Rule:MF_00852]^[1]

References

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