Identification of Neuroprotective Spoxazomicin and Oxachelin Glycosides via Chemoenzymatic Glycosyl-Scanning

J Nat Prod. 2017 Jan 27;80(1):12-18. doi: 10.1021/acs.jnatprod.6b00949. Epub 2016 Dec 28.

Abstract

The assessment of glycosyl-scanning to expand the molecular and functional diversity of metabolites from the underground coal mine fire-associated Streptomyces sp. RM-14-6 is reported. Using the engineered glycosyltransferase OleD Loki and a 2-chloro-4-nitrophenylglycoside-based screen, six metabolites were identified as substrates of OleD Loki, from which 12 corresponding metabolite glycosides were produced and characterized. This study highlights the first application of the 2-chloro-4-nitrophenylglycoside-based screen toward an unbiased set of unique microbial natural products and the first reported application of the 2-chloro-4-nitrophenylglycoside-based transglycosylation reaction for the corresponding preparative synthesis of target glycosides. Bioactivity analysis (including antibacterial, antifungal, anticancer, and EtOH damage neuroprotection assays) revealed glycosylation to attenuate the neuroprotective potency of 4, while glycosylation of the structurally related inactive spoxazomicin C (3) remarkably invoked neuroprotective activity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Antifungal Agents / chemistry
  • Antifungal Agents / isolation & purification*
  • Antifungal Agents / pharmacology*
  • Glycosides / chemistry*
  • Glycosylation
  • Molecular Structure
  • Neuroprotective Agents / chemistry
  • Neuroprotective Agents / isolation & purification*
  • Neuroprotective Agents / pharmacology*
  • Oligopeptides / chemistry
  • Oligopeptides / isolation & purification*
  • Oligopeptides / pharmacology*
  • Oxazoles / chemistry
  • Oxazoles / isolation & purification*
  • Oxazoles / pharmacology*
  • Streptomyces / chemistry*

Substances

  • Antifungal Agents
  • Glycosides
  • Neuroprotective Agents
  • Oligopeptides
  • Oxazoles
  • oxachelin
  • spoxazomicin C