The important F17 fimbriae contribution in pathogenic Escherichia coli infection

Fimbria F17 is a member of the fimbrial adhesin family expressed by pathogenic strains of Escherichia coli ( E. coli ) that are implicated in both enteric and urinary tract infections in farm animals, particularly ruminants. These fimbriae play an essential role in mediating adherence to the intestinal epithelium, thereby facilitating host colonization and contributing significantly to the pathogenesis of infection. Pathogenic E. coli strains expressing F17 fimbriae ( E. coli F17+) have been consistently associated with neonatal diarrhea and are linked to elevated mortality rates in affected animals. Despite their widespread occurrence among enteropathogenic E. coli isolates, the precise functional mechanisms and pathogenic contributions of F17 fimbriae remain insufficiently characterized. This review aims to synthesize the current body of knowledge on F17 fimbriae in E. coli , with a focus on their molecular variants, regulatory genetic pathways, host cell receptors, and epidemiological prevalence in farm animal infections.