Carba-Sugar Analogs of Glucosamine-6-Phosphate: New Activators for the glmS Riboswitch

Chemistry. 2023 Jan 12;29(3):e202202378. doi: 10.1002/chem.202202378. Epub 2022 Nov 27.

Abstract

Riboswitches are 5'-untranslated mRNA regions mostly found in bacteria. They are promising drug targets to overcome emerging bacterial resistance against commonly used antibiotics. The glmS riboswitch is unique among the family of riboswitches as it is a ribozyme that undergoes self-cleavage upon binding to glucosamine-6-phosphate (GlcN6P). Previously, we showed that carba glucosamine-6-phosphate (carba-GlcN6P) induces self-cleavage of the riboswitch with a potency similar to that of GlcN6P. Here, we report a synthetic approach to a new class of carba-GlcN6P derivatives with an alkoxy substituent in the carba position. Key features of the synthesis are a ring closing metathesis followed by a hydroboration. The strategy gives access to libraries of carba-GlcN6P derivatives. Ribozyme cleavage assays unraveled new activators for the glmS riboswitch from Listeria monocytogenes and Clostridium difficile.

Keywords: carba-sugars; carbohydrate mimics; glmS riboswitch; ribozymes.

MeSH terms

  • Bacterial Proteins / metabolism
  • Carbasugars* / metabolism
  • Glucosamine
  • Phosphates
  • RNA, Catalytic* / metabolism
  • Riboswitch*

Substances

  • Riboswitch
  • RNA, Catalytic
  • Carbasugars
  • Bacterial Proteins
  • Glucosamine
  • Phosphates