In vitro antibacterial activity of Q-35, a new fluoroquinolone.
The in vitro activity of Q-35, an 8-methoxy fluoroquinolone, was compared with those of ofloxacin, ciprofloxacin, tosufloxacin, lomefloxacin, and sparfloxacin. The MICs of Q-35 for 90% of strains tested (MIC90s) of Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, and Streptococcus pyogenes were 0.2, 6.25, 0.2, 0.39, and 0.39 micrograms/ml, respectively. The activity of Q-35 was 4- to 16-fold greater than those of ofloxacin, ciprofloxacin and lomefloxacin but equal to those of tosufloxacin and sparfloxacin against these organisms. For 82 ciprofloxacin-resistant staphylococci (MIC90 = 100 micrograms/ml), Q-35 was the most active of the new quinolones tested (MIC90 = 6.25 micrograms/ml). The MIC90s of Q-35 against Escherichia coli, Enterobacter aerogenes, and Pseudomonas aeruginosa were 0.2, 0.78, and 12.5 micrograms/ml, respectively, and Q-35 was 2- to 16-fold less active than the other quinolones tested. Q-35 showed potent bactericidal activity and inhibited the supercoiling activity of DNA gyrase of S. aureus, E. coli, and P. aeruginosa.
Ito
T
T
Department of Microbiology, Kyoto Pharmaceutical University, Japan.
Otsuki
M
M
Nishino
T
T
D000890:Anti-Infective Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000201:enzymology; D004278:DNA, Superhelical / Q000187:drug effects; D024841:Fluoroquinolones; D008826:Microbial Sensitivity Tests; D015363:Quinolones / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000201:enzymology; D059005:Topoisomerase II Inhibitors
D000890:Anti-Infective Agents; D004278:DNA, Superhelical; D024841:Fluoroquinolones; D015363:Quinolones; D059005:Topoisomerase II Inhibitors; C077155:balofloxacin