Partial chemical characterization and biological activities of sulphated glycoproteins isolated from in-vivo pilocarpine-stimulated secretions of rat minor salivary glands.

Following the incorporation of [35S]-sulphate into rats, 35S-labelled sulphated glycoproteins were isolated from the minor salivary gland secretions of pilocarpine-stimulated, immobilized animals. The secretory products were initially resolved on Sepharose 4B into two major radioactive fractions, one of which appeared at the void volume and represented only 7 per cent by weight of the applied fraction. The bulk of the products were of lower molecular weight and were further resolved by DEAE-Sephacel anion-exchange chromatography. Four distinct radioactive fractions were obtained all of which possessed blood-group A reactivity and aggregated Streptococcus sanguis NCTC 7864 but not Streptococcus mutans OMZ61. The radioactive fractions possessed protein/carbohydrate ratios in the range 1.6:1-5.8:1. Ester-sulphate contents ranged from 2.5 to 5.3 per cent with a higher value of 14.0 per cent being obtained for the most anionic fraction. Sialic acid was in the range 5.1 to 21.6 per cent. None of the fractions tested contained sulphated glycosaminoglycans.