Chemistry of the sulfate groups in a sulfated glycoprotein from rabbit submandibular gland

Abstract

A 35S-labeled sulfated glycoprotein was isolated from rabbit submandibular glands. Acid stability studies on the 35sulfate groupings present in the intact glycoprotein gave a half-life of 45 min. Partial acid hydrolysis of the 35S-labeled glycoprotein in 0.1 M HC1 for 90 min at 100 degrees C liberated a radioactive fraction which was free from peptide and fractionated in the monosaccharide range of a Sephadex G-15 column. Examination of this fraction by paper chromatography revealed the presence of a major component having the characteristics of N-acetylglucosamine 6-0-sulfate and a minor component having the properties of N-acetylgalactosamine 6-0-sulfate. The presence of ester sulfate groups in the intact glycoprotein was confirmed by infrared spectroscopy.