Identification of human salivary protease activity toward mucin: differences with caries.
A protease activity directed toward high molecular weight salivary mucus glycoprotein was identified in the secretion of human submandibular salivary gland. The protease exhibited maximum activity at pH 7.0-7.4, and following ammonium sulfate fractionation yielded an active enzyme at 60% saturation which on SDS-PAGE gave 48 and 53kDa protein bands. The enzyme exhibited serine-protease properties by showing susceptibility to phenyl methyl sulfonyl fluoride, alpha 1-antitrypsin, and egg white and soybean inhibitors. The protease activity in submandibular saliva of caries-resistant subjects was found to be 3.8-fold greater than that in saliva of caries-susceptible individuals, thus suggesting that the enzyme expression may be linked to the resistance to caries.
Piotrowski
J
J
Research Center, New Jersey Dental School, University of Medicine and Dentistry of New Jersey, Newark 07103-2400.
Czajkowski
A
A
Murty
V L
VL
Slomiany
A
A
Slomiany
B L
BL
D000328:Adult; D000645:Ammonium Sulfate / Q000737:chemistry; D003731:Dental Caries / Q000201:enzymology*; D004198:Disease Susceptibility; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D009077:Mucins / Q000378:metabolism*; D010664:Phenylmethylsulfonyl Fluoride / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology; D012463:Saliva / Q000201:enzymology*; D013363:Submandibular Gland / Q000201:enzymology* / Q000378:metabolism
D009077:Mucins; D011480:Protease Inhibitors; D010664:Phenylmethylsulfonyl Fluoride; D010450:Endopeptidases; D000645:Ammonium Sulfate