C-Nucleoside Formation in the Biosynthesis of the Antifungal Malayamycin A. Issue 4 (18th April 2019)

• Record Type: Journal Article
• Authors: Hong, Hui; Samborskyy, Markiyan; Zhou, Yongjun; Leadlay, Peter F.
• Is Part Of: Cell chemical biology. Volume 26:Issue 4(2019)
• Page Start: 493
• Page End: 501.e5
• Publication Date: 2019-04-18
• Subjects: pseudouridine synthase -- Streptomyces -- enoylpyruvyltransferase -- biosynthetic engineering -- nucleoside antibiotic -- TruD -- genome mining; Biochemistry -- Periodicals; 572.05
• DOI: 10.1016/j.chembiol.2018.12.004
• Languages: English
• ISSNs: 2451-9456

Abstract

Summary: Malayamycin A is an unusual bicyclic C-nucleoside, with interesting antiviral, antifungal, and anticancer bioactivity. We report here the discovery and characterization of the biosynthetic pathway to malayamycin by using genome mining of near-identical clusters both from the known producer Streptomyces malaysiensis and from Streptomyces chromofuscus . The key precursor 5′-pseudouridine monophosphate (5′-Ψ-MP) is supplied chiefly through the action of MalD, a TruD-like pseudouridine synthase. In vitro assays showed that MalO is an enoylpyruvyltransferase acting almost exclusively on 5′-Ψ-MP rather than 5′-UMP, while in contrast the counterpart enzyme NikO in the nikkomycin pathway readily accepts either substrate. As a result, deletion of malD in S . chromofuscus coupled with introduction of the gene for NikO led to production of non-natural N-malayamycin, as well as malayamycin A. Conversely, cloning malO into the nikkomycin producer Streptomyces tendae in place of nikO diverted biosynthesis toward C-nucleoside formation. Graphical Abstract: Highlights: The gene cluster for the antifungal C-nucleoside malayamycin A has been identified 5′-Pseudouridine monophosphate (5′-Ψ-MP) is an essential precursor 3′-Enoylpyruvyltransferase MalO specifically acts on 5′-Ψ-MP, not UMP An engineered strain produces the non-natural N-linked analog of malayamycin A Abstract : Hong et al. report the mal biosynthetic gene cluster for the antifungal C-nucleoside malayamycin A and show that the gatekeeper of C-nucleoside formation is a 3′-enoylpyruvyltransferase acting on 5′-pseudouridine monophosphate (5′-Ψ-MP) and not on 5′-UMP. These insights have allowed engineering of the malayamycin pathway to create analogs by fermentation.