Pyelonephritis-associated fimbriae (P-fimbriae) (P-fimbriae)

Pyelonephritis-associated fimbriae (P-fimbriae) are hair-like surface appendages primarily expressed by uropathogenic Escherichia coli (UPEC) (Roberts et al., 1994, PMID: 7914834). These structures are essential virulence factors that facilitate the colonization of the upper urinary tract by binding specifically to α-D-galactopyranosyl-(1-4)-β-D-galactopyranoside (galabiose) motifs found on the P-blood group antigen of human uroepithelial cells (Dodson et al., 2001, PMID: 11452310). The binding is mediated by the PapG adhesin, a lectin-like protein located at the distal tip of the fimbrial shaft (UniProt: P06746). This attachment allows the bacteria to resist the shearing forces of urine flow, promoting tissue invasion and the development of acute pyelonephritis. Because P-fimbriae are critical for the initiation of infection, they are significant targets for anti-adhesion therapies. Such therapies include galabioside mimetics and pilicides, which aim to prevent infection without the selective pressure of traditional antibiotics (Pinkner et al., 2006, PMID: 16763154). Research into these inhibitors focuses on reducing the incidence of recurrent urinary tract infections and preventing urosepsis. These agents represent a promising non-antibiotic approach to managing bacterial infections by targeting specific colonization mechanisms.

Other names

Pap piliPyelonephritis-associated piliGal-Gal piliP-piliGalabiose-binding fimbriae

Competitive inhibition of the PapG adhesin binding to host cell galabiose receptors, preventing bacterial attachment and colonization (Dodson et al., 2001, PMID: 11452310). Pilicides specifically interfere with the chaperone-usher pathway required for fimbrial assembly (Pinkner et al., 2006, PMID: 16763154).