[Modulation of P-fimbriation by ciprofloxacin in uropathogenic Escherichia coli].
BACKGROUND
The aim of this study was to determine the effect of ciprofloxacin at subinhibitory concentrations on the expression of P fimbriae of uropathogenic Escherichia coli. Thirty-nine strains of Escherichia coli isolated from out patients with urinary tract infection were studied. Thirty-nine of these strains had been previously characterized as P-fimbriated and the remaining non fimbriated strain was used as a negative control.


METHODS
Fimbriation was quantitatively studied by electron microscope observation of the strains before and after treatment. To determine possible qualitative variations in the fimbrial proteins and in the external membrane (OMPs), extraction and electrophoretic separation was performed in polyacrylamide gels.


RESULTS
No qualitative differences were observed in the OMPs profile and fimbrial proteins induced by ciprofloxacin in any of the strains studied. However, electron microscopic observation generally showed a decrease in the percentage fimbriated bacterial cells by the antimicrobial effect.


CONCLUSIONS
The mechanism of action of ciprofloxacin at subinhibitory doses may correspond to a process of fimbrial protein synthesis inhibition secondary to the initiation of general repair mechanism of the cell exposed to the antimicrobial and not to a process of specific mutations which qualitatively affect fimbrial protein composition.
Abalia
I
I
Departamento de Enfermería I, Facultad de Medicina, Universidad del País Vasco (UPV/EHU), Leioa.
Rodríguez
E
E
Umaran
A
A
Lacalle
J
J
Sarasua
A
A
Huarte
M
M
Ramón Bilbao
J
J
D000890:Anti-Infective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001422:Bacterial Adhesion / Q000187:drug effects; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis / Q000235:genetics; D002939:Ciprofloxacin / Q000494:pharmacology* / Q000627:therapeutic use; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity / Q000648:ultrastructure; D010861:Fimbriae, Bacterial / Q000187:drug effects*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D006801:Humans; D012703:Serotyping; D014552:Urinary Tract Infections / Q000382:microbiology; D014774:Virulence / Q000187:drug effects
D000890:Anti-Infective Agents; D001425:Bacterial Outer Membrane Proteins; D002939:Ciprofloxacin