Lactobacillus spp. derived biosurfactants effect on expression of genes involved in Proteus mirabilis biofilm formation.

Nosocomial infections (NIs) have been defined as infections ocuurring shortly after hospitalization or discharging from the hospital. It is associated with increased morbidities and mortalities. Proteus mirabilis considered as the hospital-acquired pathogen. The purpose of this study was to investigate the effect of Lactobacillus acidophilus-derived biosurfactant on P. mirabilis biofilm formation and flhDC/rsmA expression level (P. mirabilis standard strain ATCC 7002 and urinary infection isolated P. mirabilis strains). One of the potential strategies for the prevention of nosocomial infections is the use of probiotics. L. acidophilus was selected as a probiotic strain to produce biosurfactants. A biosurfactant reduces the adhesion of strains to microtiter plate and glass slide surfaces due to the reduction of surface tension. By using Real time PCR quantitation method we showed that biosurfactant significantly reduced rsmA expression whereas increased flhDC expression in P. mirabilis isolates. Several properties of P. mirabilis cells (biofilm formation, adhesion, and gene expression) were changed after L. acidophilus- derived biosurfactant treatment. In this study we showed that biosurfacant treatment can pave the way for a possible control of biofilm development. Based on our findings, we suggest that the prepared biosurfactant may interfere with adhesion of P. mirabilis to catheters and other devices.