Salmonella typhimurium gyrA mutations associated with fluoroquinolone resistance.
نویسندگان
چکیده
Spontaneous quinolone-resistant mutants obtained from Salmonella typhimurium Su694 were screened for mutations by direct DNA sequencing of an amplified PCR gyrA fragment. Substitutions Ser-83-->Phe (Ser83Phe), Ser83Tyr, Asp87Tyr, and Asp87Asn and double mutation Ala67Pro-Gly81Ser, which resulted in decreased sensitivities to ciprofloxacin, enoxacin, pefloxacin, norfloxacin, ofloxacin, and nalidixic acid, were found. The levels of resistance to quinolones for each mutant were determined.
منابع مشابه
Contribution of target gene mutations and efflux to decreased susceptibility of Salmonella enterica serovar typhimurium to fluoroquinolones and other antimicrobials.
The mechanisms involved in fluoroquinolone resistance in Salmonella enterica include target alterations and overexpression of efflux pumps. The present study evaluated the role of known and putative multidrug resistance efflux pumps and mutations in topoisomerase genes among laboratory-selected and naturally occurring fluoroquinolone-resistant Salmonella enterica serovar Typhimurium strains. St...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 39 7 شماره
صفحات -
تاریخ انتشار 1995