Closthioamide: An Unprecedented Polythioamide Antibiotic from the Strictly Anaerobic Bacterium Clostridium cellulolyticum

Choose sulfur in an oxygen-free world: Closthioamide (1) was isolated from the anaerobe Clostridium cellulolyticum (see SEM image) after the induction of its biosynthesis with an aqueous soil extract. An unprecedented type of symmetrical natural product in which all building blocks are connected through thioamide linkages, 1 is active against multiresistant staphylococci. It is the only known secondary metabolite from a strictly anaerobic bacterium.