High-level resistance to gentamicin in clinical isolates of enterococci.
Nine clinical isolates of Streptococcus faecalis from a university hospital were found to be resistant to high levels (minimal inhibitory concentration, greater than 2,000 micrograms/ml) of gentamicin, tobramycin, amikacin, streptomycin, and kanamycin. The high-level resistance to these aminoglycosides and resistance to penicillin-aminoglycoside synergism were transferable by conjugation to a susceptible recipient strain. In three strains tested, the aminoglycoside resistance was mediated by four aminoglycoside-modifying enzymes: a 3'-phosphotransferase transferred from two strains, a 2"-phosphotransferase and a 6'-acetyltransferase transferred from all three strains, and a streptomycin adenylyltransferase transferred from two strains. This is the first report of the occurrence of high-level gentamicin resistance in enterococcal isolates from the United States.
D000617:Aminoglycosides / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003227:Conjugation, Genetic; D004352:Drug Resistance, Microbial; D004357:Drug Synergism; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D005839:Gentamicins / Q000494:pharmacology*; D006785:Hospitals, University; D008826:Microbial Sensitivity Tests; D011815:R Factors; D014166:Transferases / Q000032:analysis; D014481:United States
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D005839:Gentamicins; D014166:Transferases