The cfr and cfr-like multiple resistance genes.

The Cfr methyl transferase causes an RNA methylation of the bacterial ribosomes impeding reduced or abolished binding of many antibiotics acting at the peptidyl transferase center. It provides multi-resistance to eight classes of antibiotics, most of which are in clinical and veterinary use. The cfr gene is found in various bacteria in many geographical locations and placed on plasmids or associated with transposons. Cfr-related genes providing similar resistance have been identified in Bacillales, and now also in the pathogens Clostridium difficile and Enterococcus faecium. In addition, the presence of the cfr gene has been detected in harbours and food markets.