Chlorhexidine hypersensitivity of ciprofloxacin-resistant variants of Pseudomonas aeruginosa PAO.
Examination of 67 ciprofloxacin-resistant clones of Pseudomonas aeruginosa PAO (ciprofloxacin MIC > 0.5 mg/L) yielded four isolates that were hypersensitive to chlorhexidine (MIC 5 mg/L); none was found among 179 ciprofloxacin-sensitive colonies. Revertant studies and the introduction of a wild-type Escherichia coli DNA gyrase A gene confirmed that ciprofloxacin resistance and chlorhexidine hypersensitivity were not the result of a single mutation. Mutagenicity testing of ciprofloxacin showed no evidence for the supposition that chlorhexidine hypersensitivity was the result of ciprofloxacin-induced mutation in P. aeruginosa PAO.
Department of Microbiology, United Medical School, Guy's Hospital, London, UK.
L W
LW
Baillie
E G
EG
Power
I
I
Phillips
D002710:Chlorhexidine / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology* / Q000633:toxicity; D004250:DNA Topoisomerases, Type II / Q000378:metabolism; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000235:genetics; D009152:Mutagenicity Tests; D010957:Plasmids; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics
D002939:Ciprofloxacin; D004250:DNA Topoisomerases, Type II; D002710:Chlorhexidine