Energy-dependent accumulation of fluoroquinolones in quinolone-resistant Klebsiella pneumoniae strains.
The intracellular accumulation of norfloxacin and pefloxacin in Klebsiella pneumoniae was evaluated. The roles of lipopolysaccharide, capsule, and outer membrane proteins were not important for the intrabacterial accumulation of fluoroquinolones in isogenic strains with known outer membrane alterations. In fluoroquinolone-resistant clinical isolates also expressing GyrA alterations, an active efflux leading to decreased accumulation of the drugs enhanced their resistance to these agents.
Martínez-Martínez
L
L
Department of Microbiology, School of Medicine, University of Seville, Spain. lmartin@cica.es
García
I
I
Ballesta
S
S
Benedí
V J
VJ
Hernández-Allés
S
S
Pascual
A
A
D000890:Anti-Infective Agents / Q000378:metabolism* / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism; D004352:Drug Resistance, Microbial / Q000502:physiology; D006801:Humans; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000378:metabolism*; D009643:Norfloxacin / Q000378:metabolism* / Q000494:pharmacology; D015366:Pefloxacin / Q000378:metabolism* / Q000494:pharmacology
D000890:Anti-Infective Agents; D015366:Pefloxacin; D009643:Norfloxacin