Antigens from human seminal plasma. Part III: studies on two new antigens from the tricholoracetic acid soluble fraction.

Two new antigens were isolated from the trichloroacetic acid soluble fraction of human seminal plasma: a polysaccharide (G-3) and a glycopeptide (G-4). Both were homogeneous, and hand sedimentation constants at infinite dilution of 2.9 X 10(-13) and 2.0 X 10(-13) resectively. Chemical and physicochemical studies suggest that both are branched molecules composed mainly of alpha-D-glucopyranosidic residues. The peptide component of G-R contains a high proporiton of the basic amino acids arginine and lysine. Since both antigens are polydispered, the low percentage of sialic acids or of some amino acids determined might have antigenic significance.