Molecular characterization of the R factors implicated in the carbenicillin resistance of a sequence of Pseudomonas aeruginosa strains isolated from burns.
An outbreak of R-factor-mediated carbenicillin resistance in Pseudomonas aeruginosa in burned patients in March 1969 was followed by a second outbreak 6 months later. No R-factor-carrying P. aeruginosa strains were detected in the intervening period but R-factor-determined lactamase was commonly encountered, particularly in Klebsiella aerogenes strains. A comparison of the molecular properties of the R factors in pseudomonads from the first and second phases with those in the Klebsiella strains from the intervening period showed them to be very closely related. A single R-factor type therefore may have been maintained in the Burns Unit between the two Pseudomonas outbreaks as a plasmid conferring resistance to ampicillin in K. aerogenes.
D002056:Burns / Q000382:microbiology*; D002228:Carbenicillin / Q000494:pharmacology*; D002499:Centrifugation, Density Gradient; D004269:DNA, Bacterial / Q000378:metabolism; D005111:Extrachromosomal Inheritance; D006801:Humans; D007709:Klebsiella / Q000187:drug effects; D009693:Nucleic Acid Hybridization; D010403:Penicillin Resistance; D011550:Pseudomonas aeruginosa / Q000187:drug effects*
D004269:DNA, Bacterial; D002228:Carbenicillin