Quinolone resistance of Salmonella enterica serovar Virchow isolates from humans and poultry in Israel: evidence for clonal expansion.
Salmonella enterica serovar Virchow is highly prevalent in humans and farm animals in Israel. In addition to high rates of resistance to multiple antibiotics, this serovar exhibits a high incidence of resistance to nalidixic acid. More than 90% of Salmonella serovar Virchow isolates of human and poultry origin obtained from 1997 to 2004 were resistant to nalidixic acid (MIC > or = 128 microg/ml), with reduced susceptibility to ciprofloxacin (MIC between 0.125 and 0.250 microg/ml). Most isolates belonged to two predominant, closely related pulsed-field gel electrophoresis image types. Investigation of the mechanisms of quinolone resistance revealed that this pathogen probably emerged from a parental clone that overproduced the AcrAB efflux pump and had a single point mutation in gyrA leading to the Asp87Tyr substitution. The close resemblance between human and poultry isolates points to poultry as a likely source of Salmonella serovar Virchow in the food chain.
Solnik-Isaac
Hadas
H
Department of Biotechnology and Food Engineering, Technion, Haifa, Israel.
Weinberger
Miriam
M
Tabak
Mina
M
Ben-David
Alon
A
Shachar
Dina
D
Yaron
Sima
S
D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D027081:DNA Gyrase / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D005838:Genotype; D006801:Humans; D007557:Israel / Q000453:epidemiology; D017720:Molecular Epidemiology; D017354:Point Mutation; D011200:Poultry; D015363:Quinolones / Q000494:pharmacology*; D012480:Salmonella Infections / Q000453:epidemiology / Q000382:microbiology*; D012481:Salmonella Infections, Animal / Q000453:epidemiology / Q000382:microbiology*; D019779:Salmonella enterica / Q000145:classification* / Q000187:drug effects* / Q000302:isolation & purification
C493251:AcrAB-TolC protein, Salmonella enterica; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D004269:DNA, Bacterial; D015363:Quinolones; D027081:DNA Gyrase