Structural studies of blood-group substance A from hog-stomach linings

Blood-group substance A from pooled hog-stomach linings was subjected to hydrolysis by a protease from asian influenza virus and to hydroxylaminolysis. Half of the polymer appeared in the dialyzable fraction after proteolysis. The non-dialyzable polysaccharide fragment retained only aspartic acid. Hydroxylaminolysis results in 30% yield of dialyzable products. The non-dialyzable fragment contained no aspartic acid after this cleavage. Mono- and oligosaccharides, peptides and short-chain glycopeptides were detected among the dialyzable products of hydroxylaminolysis. On the basis of the results obtained, a general plan of the structure of blood-group substance A is proposed.