INACTIVATION OF FUSIDIC ACID BY RESISTANT STREPTOMYCES STRAINS

Abstract

Streptomyces lividans and several other Streptomyces species are resistant to the steroid-like antibiotic fusidic acid. This resistance is mediated by structural modification of the antibiotic. Using TLC, CD, UV, IR, NMR and mass spectroscopy the structure of one of the resulting inactive compounds was determined. It is derived from fusidic acid by the loss of an acetyl group and the formation of a lactone ring between C-21 and C-16. In addition, helvolic acid, a compound closely related to fusidic acid, has been shown to be modified.