Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 6 3-4 2017 10 15 31 43 EN Leila Goudarzi Department of Microbiology, Faculty of Sciences, Alzahra University, Tehran, Iran. Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran. Rouha Kermanshahi Department of Microbiology, Faculty of Sciences, Alzahra University, Tehran, Iran. Zahra Moosavi-Nejad Department of Biology, Faculty of Basic Sciences, Alzahra University, Tehran, Iran. Mohammad Mehdi Soltan Dalla Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran. AND Division of Food Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.. 2017 12 17 2017 12 17 Background:    Nowadays, the use of probiotic bacteria for the prevention and treatment of urinary tract infections is growing. Lactobacillus, as probiotic bacterial genus, is well known for its benefits for the human health. Methods:      The effects of partially purified antimicrobial compounds (bacteriocins and biosurfactants) of Lactobacillus strains was assessed and their capacity to in vitro inhibit growth and urease production of various strains of Proteus spp, was studied. Inhibition of the urease production of Proteus spp. at sub-MIC levels was screened using spectrophotometry method.   Results:   Results revealed that semi-purified bacteriocins of L. acidophilus and L. plantarum showed a greater inhibitory activity on the bacterial urease, compared to biosurfactants of L. rhamnosus, L. casei and L. fermentum (P < 0.05). Conclusion:    It can be concluded that bacteriocins may affect Proteus pathogenesis by inhibition of the bacterial urease activity and therefore eliminate the stone formation by these bacteria. https://jmb.tums.ac.ir/index.php/jmb/article/view/335 https://jmb.tums.ac.ir/index.php/jmb/article/download/335/233