Open AccessMechanism of action of lomefloxacin
Author(s) -
Laura J. V. Piddock,
Matthew C. Hall,
R. Wise
Publication year - 1990
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.34.6.1088
Subject(s) - lomefloxacin , norfloxacin , escherichia coli , microbiology and biotechnology , enoxacin , nalidixic acid , staphylococcus aureus , antibacterial agent , ciprofloxacin , chemistry , enterobacteriaceae , dna gyrase , enterobacter cloacae , ofloxacin , biology , bacteria , biochemistry , antibiotics , genetics , gene
The inhibition of supercoiling activity of reconstituted Escherichia coli DNA gyrase by lomefloxacin, ciprofloxacin, and norfloxacin was determined. The concentrations of quinolones needed to inhibit DNA synthesis in Escherichia coli, Enterobacter cloacae, Serratia marcescens, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus were also measured. The kinetics of uptake of [14C]lomefloxacin and unlabeled lomefloxacin into whole cells of E. coli KL-16 and S. aureus NCTC 8532 and the induction of RecA in E. coli GC2241 were assayed. All strains had wild-type susceptibilities to quinolones. The concentration of quinolones needed to inhibit DNA synthesis by 50% correlated with the MIC for members of the family Enterobacteriaceae and P. aeruginosa. The concentration of quinolones needed to inhibit DNA synthesis by 50% for late-logarithmic-phase S. aureus also correlated with the MIC, unlike the data from early-logarithmic-phase cultures. E. coli and S. aureus showed a similar pattern of uptake kinetics of [14C]lomefloxacin and unlabeled lomefloxacin, indicating that the difference in the susceptibilities of the two species is probably due to different target site affinities. Essentially, lomefloxacin was less active than ciprofloxacin and ofloxacin and had activity similar to those of norfloxacin and enoxacin.