Nalidixic acid

Quinolone-resistant Salmonella strains which were isolated from patient's samples, and some Quinolone-sensitive strains were used for the mutations in QRDR region of gyrA, gyrB, parC and parE, and the presence of PMQR region were screened. Among twenty one strains which showed Nalidixic acid-resistance and Ciprofloxacin (MIC 0.125 - 2.0 µg/ml), 17 strains showed mutation in QRDR codon 87 of gyrA and 3 strain showed single mutation (Ser83-->Phe). Another cause of resistance-related efflux pump were studied about the expression of acrB, ramA, marA and soxS. 5 strains including Sal-KH1 and Sal-KH2 showed no increase in relative quantity analysis by using the qRT-PCR method (P < 0.05). In order to determine which gene expression is concerned with the resistance, Sal-9 isolate which showed decreased susceptibility and has no mutation in gyrA QRDR was used to make STM (MIC 8 µg/ml) and STH (MIC 16 µg/ml) Ciprofloxacin-resistant mutants. gyrA QRDR Asp87-->Gly mutation were identified in both STM and STH mutants by mutation analysis.

ITALIC! Salmonella entericasubspecies ITALIC! entericaserovar Berta has been isolated in multiple animal species and has been implicated in human disease. Here, we report a 4.7-Mbp draft genome sequence of ITALIC! S. entericaserovar Berta (ATCC strain 8392) and a nalidixic acid-resistant isolate derived from this strain.

BACKGROUND:  Enteric fever in the United States has been primarily associated with travel and with worrisome changes in global patterns of antimicrobial resistance. We present the first comprehensive report of National Typhoid and Paratyphoid Fever Surveillance System (NTPFS) data for a 5-year period (2008-2012).

OBJECTIVE: The objective was to assess the prevalence of plasmid-mediated quinolone resistance (PMQR)-producing isolates in a collection of quinolone-resistant Enterobacteriaceae of community origin isolated in Bejaia, Algeria.