The mechanism of action of EPEC is:

Ans. is 'a' i.e., Adherence to enterocytesENTEROPATHOGENIC E. COLIPathogenesis - Attaching-and-effacing histopathology.Three-stage model of EPEC pathogenesis: (i) Localized adherence(ii) Signal transduction(iii) Intimate adherence.Enteropathogenic E coli (EPEC) are an important cause of diarrhea in infants, especially in developing countries. EPEC adhere to the mucosal cells of the small bowel.Pathogenicity requires two important factors, the bundle forming pilus encoded by a plasmid EPEC adherence factor (EAF) and the chromosomal locus of enterocyte effacement (LEE) pathogenicity island that promote the tight adherence characteristic of EPEC (attachment and effacement). After attachment, there is loss of microvilli (effacement); formation of filamentous actin pedestals or cuplike structures.