Biofilm formation in uropathogenic Escherichia coli: association with adhesion factor genes

Abstract

Background/aim: Biofilm formation is a major determinant factor in the development of urinary tract infections (UTIs) byuropathogenic Escherichia coli (UPEC). Several adhesion factors are involved in attachment of bacterial cells to the urinary tract andbiofilm development.Materials and methods: The possible relationship between different adhesion factor genes (AFGs) and biofilm formation among UPECisolates was investigated. Prevalence of different AFGs including fimA, fimH, papAH, papC, papEF, sfa-S, foc/G, and bmaE and theirassociation to biofilm formation were investigated. Phenotypic expression of type 1 and P fimbriae was also investigated.Results: Our results showed that 84% of UPEC were moderate to strong biofilm producers. Prevalence of the type 1 and P fimbriaeassociated genes (fimA, fimH, papEF, papC) as well as the F1C fimbriae gene (foc/G) did not show a difference among different biofilmproducing groups, while higher prevalence of papAH, bmaE (M fimbriae), and sfaS (S-fimbriae) was observed for the strains producingmoderate to strong biofilms. Phenotypic expression of type 1 fimbriae was associated with biofilm formation, while no association wasobserved for P fimbriae.Conclusion: Different AFGs (especially M and S fimbria) and their expression levels affect the biofilm formation ability of UPEC.