Host range of the ermF rRNA methylase gene in bacteria of human and animal origin.

We screened 183 different clinical anaerobic and aerobic bacteria isolated from humans and other animals for the presence of the ermF gene using a polymerase chain reaction (PCR) assay. The ermF gene was detected in 107 (58%) clinical isolates, including 42 (61%) of 69 gram-positive bacteria and 65 (57%) of 114 gram-negative bacteria. Twenty-five ATCC isolates were also tested; 20 (80%) carried the ermF gene. The gene products from the ermF PCR from four isolates were sequenced and showed 95-99% nucleotide homology with the ermF gene and 98-99% amino acid homology with the gene product. Eleven (58%) of the 19 gram-negative donors tested were able to transfer the ermF gene. All nine (100%) of the gram-positive donors tested transferred the ermF gene, using either Enterococcus faecalis or Haemophilus influenzae as the recipients.