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Uridine 5'-diphospho (UDP)-galactose: Nacetylglucosamine galactosyltransferase was separated from human parotid saliva and partially purified. The optimum pH of the enzyme was 7.5. The enzyme required a specific acceptor, and its activity was activated by manganese and magnesium ions. [ABSTRACT FROM AUTHOR]

The galactosyltransferase has been purified from human parotid saliva by ammonium sulfate precipitation (25-70% saturation), followed by repeated affinity chromatography on Sepharose-α-lactalbumin. The molecular weight of the enzyme was estimated to be approximately 56,000. The enzyme catalyzes the transfer of galactose from UDP-galactose to the exposed N-acetylglucosamine residues derived from glycoproteins, forming a Galβ(1-4)GlcNAc linkage. [ABSTRACT FROM AUTHOR]

Beta-N-acetylglucosaminidase in human parotid saliva was separated into two subfractions by diethylaminoethanol cellulose column chromatography. One subtraction of the enzyme was isolated and purified. Disk electrophoresis showed that the purified enzyme was homogeneous. The molecular weight of this enzyme was estimated to be about 153,000 by gel filtration and dodecyl sulfate polyacrylamide gel electrophoresis. N-acetyl-β-galactosaminides also were hydrolyzed by this enzyme at the same site. [ABSTRACT FROM AUTHOR]

The peroxidase that is related to the thiocyanate-peroxidase-hydrogen peroxide anti-bacterial system in human parotid saliva was separated into three sub fractions by diethylaminoethanol (DEAE)-cellulose column chromatography. Heterogeneity was confirmed by isoelectric focusing. Three subtractions contributed to the inhibition of the growth of Lactobacillus casei ATCC 7469. [ABSTRACT FROM AUTHOR]

Purified acid phosphomonoesterase from human parotid saliva has been characterized as an acid nucleotidase of broad specificity. The enzyme exhibited a pH optimum at 5.8 with 5'-AMP and was not metal dependent. Activity was inhibited greatly by mercuric ions, sodium fluoride, and sodium tartrate. The tartrate inhibition was competitive. [ABSTRACT FROM AUTHOR]

Lysozyme from human parotid saliva was purified to the point where it was judged, by the criteria of ultracentrifugation and disk electrophoresis, to be homogeneous. The parotid lysozyme had a specific activity 3.5 times greater than that of hen egg-white lysozyme and a composition that was different, especially in regard to tyrosine, serine, and glutamic acid content. The molecular weight was determined to be around 14,300. When tryptophan residues were modified with N-bromosuccinamide, no lytic activity was found, which indicates that the tryptophan residues may play an important role in the maintenance of the parotid lysozyme activity. [ABSTRACT FROM AUTHOR]

Acid phosphomonoesterase was separated from human parotid saliva and purified. The purified enzyme was proved homogeneous on sedimentation and disk electrophoresis. The optimal pH of the enzyme was 3.3. The enzyme had no substrate specificity for phosphomonoesters and its activity was inhibited by SnF2 or NaF. [ABSTRACT FROM AUTHOR]