Role of YehD fimbriae (YDF) in enteropathogenic E. coli Infection
Enteropathogenic E. coli (EPEC) is a cause of acute watery diarrhea in infant population worldwide. EPEC colonizes the human small bowell by utilizing a variety of hair-like structures called pili, which mediate adherence to the intestinal epithelial mucosa. We recently reported a new pilus named YehD fimbriae (YDF), which is encoded by the yehABCD chromosomal operon, and is involed in cell adherence and biofilm formation of other E. coli pathogroups. To establish a potential role for YDF in EPEC’s motility, cell adherence, and biofilm, different experimental procedures were performed with wild-type EPEC strain E2348/69 and its derivative yehD knockout strain. The yehD mutant was less motile than the WT strain, suggesting a potential link between yehD and EPEC’s flagellum, the appendage that is responsible for the bacteria’s motility. Notably, this knockout strain adhered better to host cells and produced more biofilm than the WT strain. These effects might be attributed to upregulation of other adherence factors in the absence of YDF. The data indicate that YDF plays an important role in EPEC’s gut colonization strategy. Overall, these results further our understanding of EPEC pathogenesis and identifies a new potential target for vaccine development, bringing us one step closer to the creation of new therapies to prevent E. coli infantile mortality.