A New Approach for Designing A Potentially Vaccine Candidate against Urinary Tract Infection by Using Protein Display on Lacto-bacillus Surface

The prevalence of Urinary Tract Infection (UTI) is really high in the world. Escherichia coli is a major agent of UTI. One of the strategies for decreasing UTI infections is vaccine development. As the attachment is a really important stage in colonization and infection, at­tachment inhibition has an applied strategy. FimH protein is a major factor during bacterial colonization in urinary tract and could be used as a vaccine. Thus, it was considered in this research as a candidate antigen. The sequences of fimH and acmA genes were used for designing a synthetic gene. It was cloned to pET23a expression vector and transformed to E. coli (DE3) Origami. To confirm the expression of recombinant protein, SDS-PAGE and western blotting methods were used. Subsequently, recombinant protein was purified. On the other hand, Lactobacillus reuteri was cultured and mixed with FimH / AcmA recombinant protein. The rate of protein localization on lactobacillus surface was assessed using ELISA method. It was showed that the recombinant protein was expressed in E. coli (DE3) Origami and purified by affinity chromatography. Moreover, this protein could be localized on lactobacillus surface by 5 days. In current study, a fusion recombinant protein was pre­pared and displayed on L. reuteri surface. This strain could be used for animal experiment as a competitor against Uropathogenic E. coli (UPEC). Using manipulated probiotics strains instead of antibiotic ther­apy could decrease the antibiotic consumption and reduce multi-drug resistant strains.