Salivary, Mucous, and other Mammalian Body Fluid Glycoproteins

15 Salivary, Mucous, and other Mammalian Body Fluid Glycoproteins 

A review has described the viscoelastic properties of mucous secretions. Their structural variability may indicate the presence of distinct glycoprotein populations rather than a continuous series of related structures.  

Human parotid saliva has been purified using gel- and ion-exchange-chromatographic procedures, to give a family of glycoproteins with a very unusual amino-acid composition, little or no absorbance at 280 nm, and unusual staining characteristics with Coomassie Blue. Differences in charge, size, and total carbohydrate and neuraminic acid contents were noted. 

Purified human and monkey glycoproteins containing terminal neuraminic acid residues agglutinate with Streptococcus sanguis and S. mutans cells. Removal of the sialic acid residues from these glycoproteins results in the loss of agglutination of S. sanguis but not S. mutans. 

Examination of the occurrence of neuraminic acid moieties in glycoproteins from pig submandibular and rat sublingual glands indicates that one in four neuraminic acid residues in the pig glycoprotein occurs as an a-iV-acylneur-aminyl-(2 8)-7V-acylneuraminyl unit. The disaccharide is absent in the corresponding rat glycoprotein. 

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