Inhibitory effects of quinolones on pro- and eucaryotic DNA topoisomerases I and II.
As a means of gaining information on the selectivity of quinolone antibacterial agents, we examined their effect on four topoisomerases, topoisomerases I and II purified from Escherichia coli and calf thymus. The inhibition of supercoiling and relaxation activities was monitored by using the classical gel electrophoresis assay. Eight quinolones were assayed by using the four enzymes. Gyrase was much more sensitive to quinolones than the other topoisomerases which can therefore be inhibited by moderate concentrations of certain quinolones. No good correlation was observed between the activity on gyrase and on the other enzymes, since the ratio varied from 15 to more than 8,500. On the contrary, there was a good correlation between early inhibition of DNA synthesis, inhibition of gyrase, and MICs.
Moreau
N J
NJ
Centre d'Etudes et de Recherche en Chimie Organique Appliquée, Centre National de la Recherche Scientifique, Thiais, France.
Robaux
H
H
Baron
L
L
Tabary
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X
D000818:Animals; D002417:Cattle; D004247:DNA / Q000096:biosynthesis; D004264:DNA Topoisomerases, Type I / Q000187:drug effects*; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000187:drug effects; D015363:Quinolones / Q000494:pharmacology*; D013950:Thymus Gland / Q000187:drug effects / Q000201:enzymology; D059005:Topoisomerase II Inhibitors
D015363:Quinolones; D059005:Topoisomerase II Inhibitors; D004247:DNA; D004264:DNA Topoisomerases, Type I