Adsorption of urinary components influences the zeta potential of uropathogen surfaces

Abstract

Zeta potential distributions of five uropathogens were measured in urines collected after increased water intake, consumption of cranberry supplements, or intake of ascorbic acid by volunteers. Zeta potentials of bacteria in urine from ascorbic acid consumption shifted towards less negative values due to pH changes. Cranberry supplementation caused a shift in zeta potential distribution in a more positive direction possibly due to fructose and tannin metabolites, which are known to influence bacterial adhesion. The most negatively charged sub-populations of bacteria disappeared after increased water intake, believed to be caused by dilution of Tamm Horsfall Protein (THP). It is concluded that THP may adsorb to uropathogen cell surfaces to yield a more negative zeta potential, which thereby reduces uropathogen adhesion to surfaces through electrostatic repulsion. The ability to alter uropathogen cell surface properties by delivery of functional foods could have clinical significance in the pathogenesis and prevention of urinary tract infections.