Genetic analysis of a high-level vancomycin-resistant isolate of Staphylococcus aureus.
Vancomycin is usually reserved for treatment of serious infections, including those caused by multidrug-resistant Staphylococcus aureus. A clinical isolate of S. aureus with high-level resistance to vancomycin (minimal inhibitory concentration = 1024 microg/ml) was isolated in June 2002. This isolate harbored a 57.9-kilobase multiresistance conjugative plasmid within which Tn1546 (vanA) was integrated. Additional elements on the plasmid encoded resistance to trimethoprim (dfrA), beta-lactams (blaZ), aminoglycosides (aacA-aphD), and disinfectants (qacC). Genetic analyses suggest that the long-anticipated transfer of vancomycin resistance to a methicillin-resistant S. aureus occurred in vivo by interspecies transfer of Tn1546 from a co-isolate of Enterococcus faecalis.
Weigel
Linda M
LM
Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. lweigel@cdc.gov
Clewell
Don B
DB
Gill
Steven R
SR
Clark
Nancye C
NC
McDougal
Linda K
LK
Flannagan
Susan E
SE
Kolonay
James F
JF
Shetty
Jyoti
J
Killgore
George E
GE
Tenover
Fred C
FC
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics*; D019729:Carbon-Oxygen Ligases / Q000235:genetics*; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D013293:Enterococcus faecalis / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D005798:Genes, Bacterial; D006801:Humans; D016106:Methicillin Resistance / Q000235:genetics; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010957:Plasmids; D011815:R Factors; D011995:Recombination, Genetic; D006435:Renal Dialysis; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D014640:Vancomycin / Q000494:pharmacology; D020713:Vancomycin Resistance / Q000235:genetics*
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004251:DNA Transposable Elements; C071437:VanA ligase, Bacteria; D014640:Vancomycin; D019729:Carbon-Oxygen Ligases