FimA is a family of Gram-negative fimbrial component A proteins that form part of the pili. There are usually up to 1000 copies of this subunit in one pilus that form a helically wound rod onto which the tip fibrillum (FimF.FimG, FimH) is attached. Pilus subunits are translocated from the cytoplasm to the periplasm via the general secretory pathway SecYEG [1].

1: Chaperone-usher pathways: diversity and pilus assembly mechanism. Busch A, Waksman G; Philos Trans R Soc Lond B Biol Sci. 2012;367:1112-1122. PMID:22411982