Absence of Mutations in marRAB or soxRS in acrB -Overexpressing Fluoroquinolone-Resistant Clinical and Veterinary Isolates of Escherichia coli
Open Access
- 1 May 2001
- journal article
- Published by American Society for Microbiology in Antimicrobial Agents and Chemotherapy
- Vol. 45 (5), 1550-1552
- https://doi.org/10.1128/aac.45.5.1550-1552.2001
Abstract
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 overexpresssoxS, and five appeared to overexpress marA. A number of mutations were found in the marR andsoxR repressor genes, correlating with greater amounts ofmarA and soxS mRNA, respectively.Keywords
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