1. Galactoside carrier in E. Coli
2. Cell surface antigen of Brucella.
3. Structural protein in the M line of striated muscle (myomesin). (4) Cell wall protein of streptococci: antibody typing of the M protein is important in identification of different strains of Group A streptococci (at least 55 serotypes are known). The M protein confers antiphagocytic properties on the cell and is present as hair like fimbriae on the surface. M protein is an important virulence factor and antibodies directed against M protein are essential for phagocytic killing of the bacteria.
(18 Nov 1997)