Open AccessPhysical Characterization of Ten R Plasmids Obtained from an Outbreak of Nosocomial Klebsiella pneumoniae Infections
Author(s) -
Peter L. Sadowski,
Bryan C. Peterson,
Dale N. Gerding,
P. Patrick Cleary
Publication year - 1979
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.15.4.616
Subject(s) - plasmid , microbiology and biotechnology , klebsiella pneumoniae , carbenicillin , enterobacter cloacae , kanamycin , biology , amp resistance , ampicillin , escherichia coli , gentamicin , cefotaxime , antibiotics , genetics , dna , gene
Gentamicin resistance inKlebsiella pneumoniae involved in an outbreak at the Minneapolis Veterans Administration Hospital was due to a transmissible R plasmid. In addition to gentamicin, this plasmid conferred resistance to tobramycin, kanamycin, ampicillin, carbenicillin, cephalothin, chloramphenicol, and sulfathiazole. R plasmids which transferred this complex antibiogram were identified in several clinical isolates, including four different serotypes ofK. pneumoniae, Escherichia coli, Enterobacter cloacae , andProteus morganii . The covalently closed circular form of all R plasmids isolated had a sedimentation coefficient of 76S to 77S, corresponding to a molecular weight of 58 × 106 . The possibility that a single R plasmid was responsible for the dissemination of multiple drug resistance among all of these different clinical strains was examined by characterizing the plasmids by usingEco RI restriction endonuclease. The same 15 fragments were obtained from each of the 10 plasmids analyzed. Their molecular weights ranged from 4 × 105 to 11 × 106 . Thus, we conclude that each of the 10 plasmids present in the various clinical strains isolated from the hospital over a 7-month period originated from a common source and that R plasmid transfer was important in their spread.