INHIBITION OF MOTILITY AND ADHERENCE OF PROTEUS-MIRABILIS TO UROEPITHELIAL CELLS BY SUBINHIBITORY CONCENTRATIONS OF AMIKACIN

The effect of subinhibitory concentrations of amikacin on A Proteus mi rabilis motility and adherence to human uroepithelial and to HeLa cell s was compared with that of gentamicin. In addition, the effect of bot h antibiotics on cell surface hydrophobicity was also examined. Exposu re of bacterial cells in the logarithmic phase to one fourth of amikac in or gentamicin at one fourth of their respective minimal inhibitory concentrations causes the inhibition of swarming and motility of Prote us strains, Amikacin significantly reduced adhesion of Proteus strains to human uroepithelial cells and gentamicin exerts the same effect to a lesser extent. Such inhibitory concentrations of amikacin or gentam icin had no significant effect on the attachment ability of these stra ins to HeLa cells compared to the nontreated cells. Treatment of the b acterial cells with amikacin or gentamicin changed significantly the c ell surface hydrophobicity towards the hydrophilic state compared to n ontreated cells, and it was found to be strain dependent. Since motili ty and attachment ability are considered as pathogenic traits, these d ata indicate the impact of amikacin on the virulence factors especiall y in urinary tract infections with Proteus strains.