d - Galactose is attached as single residues or as 4 - O - substituted residues to the C - 3 positions of some l - rhamnose residues. (epi4dogs.com)
The researchers also identified a way to remove the problematic GlcNAc sugar so that a mutant form of the bacteria with only rhamnose - containing GAC could be purified and tested as a vaccine antigen. (sciencedaily.com)
Specifically, the researchers noted that the cell wall of strep is composed primarily of a single molecule known as the group A carbohydrate (or GAC) which, in turn, is built from repeating units of the bacterial sugar rhamnose and the human - like sugar N - acetylglucosamine (GlcNAc). (sciencedaily.com)