A thin filament that extends from the surface of a microorganism and functions to facilitate the adhesion of the cell to other cells or to the substratum. Fimbriae occur in large numbers on a given cell, and they are not to be confused with conjugative pili. Fimbriae occur on Gram- negative bacteria and certain fungi. Each fimbria consists of linear repeating molecules of a protein called fimbrillin. See P blood group, pilus.
Subjects: Genetics and Genomics.