Identification of DNA gyrase A mutations in ciprofloxacin-resistant isolates of Salmonella typhimurium from men and cattle in Germany.
Six multiply resistant isolates of Salmonella typhimurium var. copenhagen with high-level resistance to fluoroquinolones (e.g., MIC of ciprofloxacin: 32 micrograms/ml) were isolated from human patients (n = 3) and from cattle (n = 3). The isolates were examined by complementation tests using a set of broad-host-range plasmids, which carry either the gyrA+ or the gyrB+ genes or a combination of both from Escherichia coli K-12. The results indicated a combination of gyrA and gyrB mutations in all isolates. Subsequent direct sequencing of PCR-generated internal DNA fragments of gyrA revealed an identical double mutation in all six isolates (Ser-83-->Ala and Asp-87-->Asn). In addition, the results of phenotypic (i.e., phagetype, biotype, serotype) and genotypic characterization [i.e., ribotyping and polymerase chain reaction fingerprinting (PCR-fingerprinting)] were identical for all six isolates and were distinguishable from a quinolone-susceptible strain of the same serovar and an unrelated isolate of S. typhimurium. These data indicate the clonal identity of the fluoroquinolone-resistant strains of S. typhimurium isolated from men and cattle in Germany.
Heisig
P
P
Pharmazeutische Mikrobiologie, Universität Bonn, Germany.
Kratz
B
B
Halle
E
E
Gräser
Y
Y
Altwegg
M
M
Rabsch
W
W
Faber
J P
JP
D000293:Adolescent; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D002939:Ciprofloxacin / Q000494:pharmacology*; D003470:Culture Media; D004250:DNA Topoisomerases, Type II / Q000235:genetics*; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D005838:Genotype; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007202:Indicators and Reagents; D009154:Mutation; D010641:Phenotype; D016133:Polymerase Chain Reaction; D012480:Salmonella Infections / Q000453:epidemiology / Q000382:microbiology*; D012481:Salmonella Infections, Animal / Q000453:epidemiology / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000201:enzymology / Q000235:genetics*
D000890:Anti-Infective Agents; D003470:Culture Media; D004269:DNA, Bacterial; D007202:Indicators and Reagents; D002939:Ciprofloxacin; D004250:DNA Topoisomerases, Type II