BACKGROUND The detection of mutations in the gyrA and gyrB genes in the Mycobacterium tuberculosis genome that have been demonstrated to confer phenotypic resistance to fluoroquinolones is the most promising technology for rapid diagnosis of fluoroquinolone resistance. METHODS In order to characterize the diversity and frequency of gyrA and gyrB mutations and to describe the global distributi...

Ftorhinolony — osnovnaya gruppa preparatov, primenyaemyh dlya lecheniya tuberkuleza s mnozhestvennoj lekarstvennoj ustojchivost'yu (MLU-TB). Cel'yu issledovaniya bylo ocenit' raznoobrazie mutacij v gene gyrA, a takzhe ustanovit' associaciyu gyrA fenotipicheskoj k levofloksacinu i obshchim profilem ustojchivosti vozbuditelya. Issledovanie provedeno na diagnosticheskom materiale ot 2836 bol'nyh t...

AIM To analyse mutations in the gyrA and parC genes leading to possible increase in ciprofloxacin resistance (high MIC values for ciprofloxacin) in clinical isolates of Neisseria gonorrhoeae in Delhi, India. METHOD MIC of ciprofloxacin for 63 clinical isolates of N gonorrhoeae were examined by the Etest method. Subsequently, gyrA and parC genes of these isolates were amplified and sequenced f...

conclusions this study demonstrated the specificity and sensitivity of the pcr-sscp method for finding mutations in the gyra gene. due to the sensitivity of most isolates to ciprofloxacin, this antibiotic should be considered an appropriate drug for the treatment of related diseases. background during the past several years, nontuberculous mycobacteria (ntm) have been reported as some of the mo...

DNA gyrase catalyses the adenosine triphosphate-dependent introduction of negative supercoils into DNA. The enzyme binds a DNA-segment at the so-called DNA-gate and cleaves both DNA strands. DNA extending from the DNA-gate is bound at the perimeter of the cylindrical C-terminal domains (CTDs) of the GyrA subunit. The CTDs are believed to contribute to the wrapping of DNA around gyrase in a posi...

strain with no parC mutations. This is consistent with previous findings that gyrA mutations are necessary for quinolone resistance, whereas parC mutations appear to be complementary, as resistant strains do not carry parC mutations alone. – 6 Some studies further suggest that additional parC mutations facilitate increasing levels of resistance, but our study did not support this. For example, ...

During the early 1990s, a clone of multiresistant Salmonella enterica serovar Typhimurium O5 negative (var. Copenhagen) of phage type DT204c predominated in Germany and neighboring countries within the calf-fattening industry. In addition to being resistant to ampicillin, kanamycin, tetracycline, chloramphenicol, and trimethoprim, these isolates were highly resistant to nalidixic acid (MIC 128 ...

Streptococcus pneumoniae serotype 3, isolated from a penicillin-allergic patient and initially susceptible to fluoroquinolones, macrolides, lincosamides, quinupristin-dalfopristin, and telithromycin, became resistant to all these drugs during treatment. Mutations in the parC and gyrA and in the 23S rRNA and the ribosomal protein L22 genes were detected in the resistant isolates.

Ciprofloxacin is one of the most widely used antibiotics for the treatment of several infections caused by Gram-negative bacteria, like E. coli. Changes in gyrA, encoding GyrA subunit of DNA gyrase, cause the resistance to ciprofloxacin. Some ciprofloxacin resistant gyrA mutants acquired constitutive expression of marRAB operon due to the gaining mutations in marR, a repressor of this operon. T...