Issue 17, 2021

Revised structural assignment of azalomycins based on genomic and chemical analysis

Abstract

Actinobacteria have long served as sources of novel natural products with antibiotic properties, but the isolation of novel derivatives and the determination of their absolute structures have remained a scientific challenge. The objective of this study was to clarify the absolute structures of the azalomycin core structure as previous structural assignments remained controversial. Based on the isolation of four azalomycin derivatives (F4a, F4b, F5a and F5b) from the termite-associated Streptomyces sp. M56, we applied 1D and 2D nuclear magnetic resonance (NMR), J-based configuration analyses (JBCA), electronic circular dichroism (ECD), high-resolution (HR)-electrospray ionization (ESI) mass spectrometry to clarify the stereochemical assignment. These studies were supported by in silico studies of all ketoreductase and enoylreductase domains encoded within the PKS. The combined analysis allowed us to propose a revised stereochemical assignment of the four azalomycin derivatives, and bioactivity studies confirmed and expanded the antifungal and antiproliferative properties of azalomycins.

Graphical abstract: Revised structural assignment of azalomycins based on genomic and chemical analysis

Supplementary files

Article information

Article type
Research Article
Submitted
20 Apr 2021
Accepted
16 Jun 2021
First published
17 Jun 2021

Org. Chem. Front., 2021,8, 4791-4798

Revised structural assignment of azalomycins based on genomic and chemical analysis

S. R. Lee, H. Guo, J. S. Yu, M. Park, H. Dahse, W. H. Jung, C. Beemelmanns and K. H. Kim, Org. Chem. Front., 2021, 8, 4791 DOI: 10.1039/D1QO00610J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements