Targeting of DNA gyrase in Streptococcus pneumoniae by sparfloxacin: selective targeting of gyrase or topoisomerase IV by quinolones.
نویسندگان
چکیده
gyrA and parC mutations have been identified inn Streptococcus pneumoniae mutants stepwise selected for resistance to sparfloxacin, an antipneumococcal fluoroquinolone. GyrA mutations (at the position equivalent to resistance hot spot Ser-83 in Escherichia coli GyrA) were found in all 17 first-step mutants examined and preceded DNA topoisomerase IV parC mutations (at Ser-79 or Glu-83), which appeared only in second-step mutants. The targeting of gyrase by sparfloxacin in S. pneumoniae but of topoisomerase IV by ciprofloxacin indicates that target preference can be altered by changes in quinolone structure.
منابع مشابه
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متن کامل101-106 Paper 13 Suppl. A
The quinolones inhibit the essential bacterial enzymes DNA gyrase and topoisomerase IV, which alter DNA topology after inserting a double-stranded break. DNA gyrase exists as an A2B2 tetramer, encoded by the gyrA and gyrB genes, and catalyses negative DNA supercoiling. Topoisomerase IV exists as a C2E2 tetramer encoded by the parC and parE genes, and is involved in chromosome partitioning. Prev...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 41 2 شماره
صفحات -
تاریخ انتشار 1997