Concurrent modifications of the C-terminus and side ring of thiostrepton and their synergistic effects with respect to improving antibacterial activities†
Abstract
The double-mutant strain Streptomyces laurentii ΔtsrB/T was designed and constructed based on a recent understanding regarding the structure–activity relationship of thiostrepton (TSR) against prokaryotic pathogens. Five new C-terminally methylated TSR (CmTSR) derivatives that varied in the side-ring structure were obtained via the chemical feeding of quinaldic acid (QA) analogs. These derivatives provide new insights into the tolerance of QA incorporation in TSR biosynthesis. Certain members of the tested TSR derivatives, meanwhile, exhibited much better antibacterial activities than all currently known thiopeptide antibiotics.
- This article is part of the themed collection: Celebrating 70 Years of Shanghai Institute of Organic Chemistry