Probably a component of the fimbrium tip (PubMed:17526848, PubMed:19506009). These long, filamentous pili are attached to the cell surface; they mediate biofilm formation, adhesion onto host cells and onto other bacteria that are part of the oral microbiome (PubMed:17526848). They play an important role in invasion of periodontal tissues and are major virulence factors. FimC, FimD and FimE contribute to interaction with host CXCR4 and thereby down-regulate the TLR2-mediated host immune response (PubMed:17675496, PubMed:19506009). Fimbriae are composed of a major, structural subunit and the minor components FimC, FimD and FimE (PubMed:17526848, PubMed:19506009). Identified in a complex composed of FimC, FimD and FimE (in vitro) (PubMed:19506009). The complex interacts with host extracellular matrix proteins, including fibronectin and type I collagen (PubMed:17526848, PubMed:19506009). Interacts with host CXCR4 (PubMed:19506009). Probably synthesized as a palmitoylated precursor. Efficient export to the outer membrane and integration into fimbriae requires lipidation and subsequent proteolytic removal of the lipidated propeptide (Probable). Probably part of the fimbrium tip, as a part of the complex formed by FimC, FimD and FimE. Triple mutants lacking FimC, FimD and FimE show strongly decreased interaction with host CXCR4 and impaired down-regulation of the TLR2-mediated innate immune response, resulting in strongly reduced survival of the bacteria. The name (major fimbrium subunit) does not indicate the abundance of the protein, but is derived from the greater length of the major fimbriae. In strain ATCC 33277 and strain ATCC BAA-1703 / FDC 381, major fimbriae are 300 - 1600 nM in length and about 5 nm in diameter. In contrast, minor fimbriae are only about 80 - 120 nm long. This length difference is observed only in a small number of strains, including strain ATCC 33277 and strain ATCC BAA-1703 / FDC 381, and is due to a loss of function mutation in FimB, a protein that restricts fimbrial length in other strains. Belongs to the FimD family. A loosening of habits - Issue 182 of August 2016