The isolation and structure elucidation of four new naturally occurring amino-nucleoside [puromycins B-E (1-4)] metabolites from a Himalayan isolate (Streptomyces sp. PU-14-G, isolated from the Bara Gali region of northern Pakistan) is reported. Consistent with prior reports, comparative antimicrobial assays revealed the need for the free 2″-amine for anti-Gram-positive bacteria and antimycobacterial activity. Similarly, comparative cancer cell line cytotoxicity assays highlighted the importance of the puromycin-free 2″-amine and the impact of 3′-nucleoside substitution. These studies extend the repertoire of known naturally occurring puromycins and their corresponding SAR. Notably, 1 represents the first reported naturally occurring bacterial puromycin-related metabolite with a 3′-N-amino acid substitution that differs from the 3′-N-tyrosinyl of classical puromycin-type natural products. This discovery suggests the biosynthesis of 1 in Streptomyces sp. PU-14G may invoke a uniquely permissive amino-nucleoside synthetase and/or multiple synthetases and sets the stage for further studies to elucidate, and potentially exploit, new biocatalysts for puromycin chemoenzymatic diversification.
|Number of pages||7|
|Journal||Journal of Natural Products|
|State||Published - Nov 26 2018|
Bibliographical notePublisher Copyright:
Copyright © 2018 American Chemical Society and American Society of Pharmacognosy.
ASJC Scopus subject areas
- Analytical Chemistry
- Molecular Medicine
- Pharmaceutical Science
- Drug Discovery
- Complementary and alternative medicine
- Organic Chemistry