title: Characterization of a nosocomially significant, multiple drug-resistant strain of Serratia marcescens.
abstract: A multiple drug-resistant strain of Serratia marcescens (bacteriocin type 18) was isolated from three clinical patients. The isolates were found to carry a conjugally nontransferable, nonmobilizeable resistance plasmid (R-plasmid) with resistance-(r)-determinants against ten antimicrobial drugs: ampicillin, carbenicillin, chloramphenicol, gentamicin, kanamycin, neomycin, streptomycin, tobramycin, triple sulfonamides, cotrimoxazole, and--possibly--nalidixic acid, as determined with exposure to 'curing' agents (ethidium bromide, acridine orange, and sodium dodecyl sulfate) and by the high rate of spontaneous loss of r-determinants. Dyebuoyant density centrifugation allowed recovery of R-plasmid DNA that measured roughly 24 mum in contour length; after 'curing' with concomitant loss of 9 r-determinants, the contour length of the R-plasmid DNA of one isolate (No. SE 154) had decreased to roughly 15 mum, and none was detected in the sole variant of the isolate that spontaneously had lost 11 r-determinants.
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D002228:Carbenicillin / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D004269:DNA, Bacterial / Q000032:analysis; D004270:DNA, Circular / Q000032:analysis; D005839:Gentamicins / Q000494:pharmacology; D006801:Humans; D007612:Kanamycin / Q000494:pharmacology; D009268:Nalidixic Acid / Q000494:pharmacology; D009355:Neomycin / Q000494:pharmacology; D010403:Penicillin Resistance; D011113:Polymyxins / Q000494:pharmacology; D012706:Serratia marcescens / Q000032:analysis / Q000187:drug effects / Q000302:isolation & purification; D013307:Streptomycin / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D014031:Tobramycin / Q000494:pharmacology
chemical_list: D004269:DNA, Bacterial; D004270:DNA, Circular; D005839:Gentamicins; D011113:Polymyxins; D013449:Sulfonamides; D009268:Nalidixic Acid; D007612:Kanamycin; D002701:Chloramphenicol; D000667:Ampicillin; D002228:Carbenicillin; D009355:Neomycin; D014031:Tobramycin; D013307:Streptomycin