Distribution and Composition of Sialic Acids and Glycoproteins

摘要

A direct demonstration was made for the first time that the principal type of linkage between carbohydrate side chains of bovine submaxillary mucin and the main peptide chain are glycosidic linkages between N-acetyl galactosamine and the hydroxyl groups of serine and threonine. Apparently such linkages are widely distributed in glycoproteins, and a direct semi-quantitative method was developed to show the presence of such linkages. Indirect evidence was also obtained that a minor proportion of ester linkages to glutamic and aspartic acids may be present. A third type of linkage is not ruled out. Partial purification of an L-fucosidase from abalone liver was accomplished. At least two types are present, one working on simple L-fucosides and the other on mucin fucoside linkages. (Author)