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...

We describe a system that allows us to easily isolate and characterize mutants in yeast topoisomerase II that are resistant to antitumor agents that target this enzyme. The system uses yeast strains that are sensitive to those agents and that carry temperature-sensitive top2 mutations. The temperature-sensitive mutation allows the isolation of recessive drug-resistant mutations. The mutagenized...

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...

AIM The purpose of this study was to determine how various compounds known to be positive mutagens, contribute to the development of mutations leading to ciprofloxacin resistance in Salmonella enterica subsp. enterica serotype Typhimurium. The molecular mechanism of ciprofloxacin resistance in treated strains was investigated. METHODS A modified version of the incorporation plate test was use...

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, ...

The potential for genetic modification of biological warfare agents makes rapid identification of antibiotic resistant strains critical for the implementation of suitable infection control measures. The fluorinated quinolone, ciprofloxacin, is an antibiotic effective for treating bacterial infections by inhibiting the enzyme activity of the DNA type II topoisomerases DNA gyrase and topoisomeras...