Fimbrial adhesin of Enterobacteriaceae

Fimbrial adhesins are specialized proteins located at the distal tips of fimbriae (pili) on the surface of bacteria within the Enterobacteriaceae family, including Escherichia coli and Klebsiella pneumoniae (UniProt, P08191). These proteins function as lectins that recognize and bind to specific carbohydrate moieties on host cell surfaces, such as mannose or galabiose (PubMed, PMID: 29109227). This binding event is the critical first step in bacterial colonization, allowing the pathogen to adhere to epithelial tissues and resist mechanical clearance by host fluids like urine or mucus (NIH, StatPearls). For example, the FimH adhesin is essential for the establishment of urinary tract infections (UTIs) by binding to uroplakins in the bladder (PubMed, PMID: 30254244). Beyond simple attachment, fimbrial adhesins can trigger host cell signaling pathways that facilitate bacterial invasion and the formation of intracellular bacterial communities (PubMed, PMID: 25631567). Because of their role in pathogenesis, these adhesins are major targets for anti-adhesion therapies, which aim to prevent or treat infections without using traditional antibiotics (Nature Reviews Microbiology, 2017). Small molecule inhibitors, such as mannosides like Sibofimloc (EB8018) and GSK3882347, are designed to competitively occupy the adhesin's binding pocket, thereby blocking bacterial attachment (ClinicalTrials.gov, NCT03943446). This therapeutic approach is particularly promising for managing recurrent UTIs and inflammatory bowel diseases associated with Adherent-Invasive E. coli (AIEC) (PubMed, PMID: 31506579).

Other names

FimHPapGMrkDType 1 fimbrial adhesinP-fimbrial adhesinBacterial adhesinPili adhesin

Competitive inhibition of bacterial attachment to host cell receptors (anti-adhesion).