Zusammenfassung
Of 94 clinical isolates of Staphylococcus aureus (n = 51) acid coagulase-negative staphylococci (CNS) (n 43), mutations in the quinolone resistance-determining region of topoisomerases Gr1A, Gr1B, GyrA, and GyrB together with MICs of six quinolones were analyzed. Amino acid substitutions at identical residues (Gr1A residues 80 and 84; GyrA residues 83 and 88) were found in S, aureus and CNS, ...
Zusammenfassung
Of 94 clinical isolates of Staphylococcus aureus (n = 51) acid coagulase-negative staphylococci (CNS) (n 43), mutations in the quinolone resistance-determining region of topoisomerases Gr1A, Gr1B, GyrA, and GyrB together with MICs of six quinolones were analyzed. Amino acid substitutions at identical residues (Gr1A residues 80 and 84; GyrA residues 83 and 88) were found in S, aureus and CNS, Active efflux, as suggested by blocking by reserpine, contributed substantially to the resistance phenotype in some strains. Among ciprofloxacin, clinafloxacin, levofloxacin, nalidixic acid, trovafloxacin, and sparfloxacin, a 0.5-mug/ml concentration of sparfloxacin discriminated best between strains with two or three mutations and those with no mutations.
Altmetric