Comparison and application of ribosome spacer DNA amplicon polymorphisms and pulsed-field gel electrophoresis for differentiation of methicillin-resistant Staphylococcus aureus strains.
Analysis of sequences in the fragments of the 16S-23S rRNA intergenic spacer region by the ribosome spacer PCR (RS-PCR) can differentiate strains of methicillin-resistant Staphylococcus aureus (MRSA). We compared this technique with pulsed-field gel electrophoresis (PFGE) for typing MRSA strains and its application during an investigation of an outbreak. A total of 180 isolates of MRSA collected from various hospital laboratories within the United Kingdom and elsewhere were typed by PFGE and RS-PCR. PFGE identified 17 different types among the 180 strains examined, and RS-PCR generated 13 different types. PFGE could detect minor genetic variations among the isolates and could identify the variants which were not discriminated by RS-PCR. Four unique strain types detected by PFGE were not detected by RS-PCR. When applied to typing the outbreak-related strains from the vascular surgery unit at the General Infirmary at Leeds, the results of RS-PCR were identical to those of PFGE. Our results have shown that RS-PCR is a rapid, inexpensive technique that is highly reproducible and almost as discriminatory as PFGE for typing MRSA isolates and should be useful in the local investigation of MRSA outbreaks.
Kumari
D N
DN
Department of Microbiology, University of Leeds, United Kingdom.
Keer
V
V
Hawkey
P M
PM
Parnell
P
P
Joseph
N
N
Richardson
J F
JF
Cookson
B
B
D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics*; D004352:Drug Resistance, Microbial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D008712:Methicillin / Q000494:pharmacology*; D010406:Penicillins / Q000494:pharmacology*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011110:Polymorphism, Genetic; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics
D004269:DNA, Bacterial; D010406:Penicillins; D008712:Methicillin