Effect of fluoroquinolone concentration on selection of resistant mutants of Mycobacterium bovis BCG and Staphylococcus aureus.
When Mycobacterium bovis BCG and Staphylococcus aureus were plated on agar containing increasing concentrations of fluoroquinolone, colony numbers exhibited a sharp drop, followed by a plateau and a second sharp drop. The plateau region correlated with the presence of first-step resistant mutants. Mutants were not recovered at concentrations above those required for the second sharp drop, thereby defining a mutant prevention concentration (MPC). A C-8-methoxy group lowered the MPC for an N-1-cyclopropyl fluoroquinolone.
Dong
Y
Y
Public Health Research Institute, New York, New York 10016, USA.
Zhao
X
X
Domagala
J
J
Drlica
K
K
D000890:Anti-Infective Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004352:Drug Resistance, Microbial / Q000235:genetics; D024841:Fluoroquinolones; D008826:Microbial Sensitivity Tests; D009163:Mycobacterium bovis / Q000187:drug effects*; D013211:Staphylococcus aureus / Q000187:drug effects*; D013329:Structure-Activity Relationship
D000890:Anti-Infective Agents; D024841:Fluoroquinolones