Glycoproteins salivary

Saliva. The salivary glands produce a slightly alkaline secretion which—in addition to water and salts—contains glycoproteins (mucins) as lubricants, antibodies, and enzymes. a-Amylase attacks polysaccharides, and a lipase hydrolyzes a small proportion of the neutral fats. a-Amylase and lysozyme, a mu-rein-cleaving enzyme (see p. 40), probably serve to regulate the oral bacterial flora rather than for digestion (see p. 340). 

Gillece-Castro BL, Prakobphol A, Burlingame AL, Lefller H, Fisher SJ. Structure and bacterial receptor activity of a human salivary proline-rich glycoprotein. J. Biol. Chem. 1991 266 17358— 17368... 

According to Rolla, ionic bonds are important in the associations between bacterial polysaccharides and protein-coated tooth surfaces (21). This was based on in vitro experiments on the afiinity of dextran for hydroxyapatite powder coated with salivary glycoprotein specifically, adsorption of dextran was inhibited by 0.5M. Prior treatment of the coated hydroxyapatite with neuraminidase also reduced adsorption of dextran. Neuraminidase would be expected to reduce the negative charge of the protein coat by removing ionized sialic acid moieties. Of course, reduced adsorption of dextran could result from conformational changes induced in the pellicle protein by the neuraminidase treatment, as was apparently effected by 4M or 8M urea, in other experiments. 

Thus, in plaque, both carbohydrate and protein material contribute to the matrix. While the origins of these components have been indicated, other hypotheses were advanced to explain incorporation of salivary proteins in plaque (IS). For example, Leach has proposed that plaque proteins arise as a result of the action of glycosidases e.g., neuraminidase) on salivary glycoproteins (5). Data of Briscoe et al. suggest, however, that neuraminidase does not modify adsorption behavior of salivary proteins (22). 

Saliva, pH 7, contains ptyalin (salivary amylase), digests starches. Mucin, a glycoprotein, lubricates food and may interact with drugs... 

Some glycoproteins, particularly those with numerous, generally distributed, oligosaccharide side-chains, are able to form dispersions with stringy characteristics, as in nasal mucus or salivary discharges. The rheological implications of interactions between mucus and dmgs have been studied. As yet there is no coherent view as to what the ideal mucolytic... 

Salivary Specimens. Cortisol is stable in saliva for 1 week at 4 °C and for 4 months when stored frozen. Freezing of specimens is recommended because it leads to precipitation of salivary glycoproteins and leaves a nonviscous liquid for pipetting. ... 

Of interest, lipid-containing pellicle was less permeable to lactic acid diffusion in vitro than lipid-depleted pellicle and pellicles from caries-resistant subjects were less permeable than pellicles from caries-susceptible subjects [102], These observations suggest a possible protection mechanism against caries without highlighting the particular lipids responsible. Other studies have indicated that lipids adversely affect the association of calcium with salivary glycoprotein [105]. It has also been speculated that because lipids modify the hydrophobic nature of the pellicle, they may facilitate bacterial adhesion [102,105],... 

Several studies have been performed in order to determine the protein composition of the in vivo-formed salivary pellicle, using amino acid analysis and immunological, histochemical, chromatographic and electrophoretic methods [2-5, 7-13, 39-41, 46, 47, 48-52], In general, these studies indicate that proteins and glycoproteins are the major salivary components of the in vivo pellicle. A large number of specific proteins involved in pellicle formation in vivo have been identified by the methods used in the above-mentioned studies and these are summarised in table 1. 

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