Absence of mutations in marRAB or soxRS in acrB-overexpressing fluoroquinolone-resistant clinical and veterinary isolates of Escherichia coli.
نویسندگان
چکیده
The amount of acrB, marA, and soxS mRNA was determined in 36 fluoroquinolone-resistant E. coli from humans and animals, 27 of which displayed a multiple-resistance phenotype. acrB mRNA was elevated in 11 of 36 strains. A mutation at codon 45 (Arg-->Cys) in acrR was found in 6 of these 11 strains. Ten of the 36 isolates appeared to overexpress soxS, and five appeared to overexpress marA. A number of mutations were found in the marR and soxR repressor genes, correlating with greater amounts of marA and soxS mRNA, respectively.
منابع مشابه
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 45 5 شماره
صفحات -
تاریخ انتشار 2001