Elucidation of the Late Steps during Hexacosalactone A Biosynthesis in Streptomyces samsunensis OUCT16-12.

ABSTRACT: Hexacosalactone A (1) is a polyene macrolide compound featuring a 2-amino-3-hydroxycyclopent-2-enone (C₅N)-fumaryl moiety. While compound 1 has been proposed to be assembled via a type I modular polyketide synthase (PKS) system, most of the putative biosynthetic steps lack experimental evidence. In this study, we elucidated the post-PKS tailoring steps of compound 1 through in vivo gene inactivation and in vitro biochemical assays. We demonstrated that the amide synthetase HexB and O-methyltransferase HexF are responsible for the installations of the C₅N moiety and the methyl group at 15-OH of compound 1, respectively; two new hexacosalactone analogs, named hexacosalactones B (4) and C (5), were purified and structurally characterized, followed by

SUBMITTER: Duan H 

PROVIDER: S-EPMC10057877 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature