Effect of sub-minimum inhibitory concentrations of ciprofloxacin, amikacin and colistin on biofilm formation and virulence factors of Escherichia coli planktonic and biofilm forms isolated from human urine

The aim of this study was to determine the effect of subinhibitory concentrations (sub-MICs) of ciprofloxacin, amikacin and colistin on biofilm formation, motility, curli fimbriae formation by planktonic and biofilm cells of E. coli strains isolated from the urine of patients with various urinary system infections. Quantification of biofilm formation was carried out using a microtiter plate assay and a spectrophotometric method. Bacterial enumeration was used to assess the viability of bacteria in the biofilm. Curli expression was determined by using YESCA agar supplemented with congo red. Usi...

Texto completo