Abstract
Protein A and C, which are major components of the acidic proline-rich proteins in human saliva, were digested, before or after adsorption to hydroxyapatite, with alkaline phosphatase, trypsin, thermolysin and a proteinase preparation from salivary sediment. The results demonstrate that the binding site is located in the proline-poor N-terminal part of the protein, possibly between residues 3 and 25. Phosphoserine is necessary for maximal adsorption of the proteins to hydroxyapatite. When proteins A and C are adsorbed to hydroxyapatite before proteolytic digestion there is a protection of some of the susceptible bonds in the N-terminal part of the proteins and a gradual removal of the proline-rich C-terminal part. Thermolysin can cleave susceptible bonds in the part of the protein that remains bound to hydroxyapatite, but at least some of the resulting peptides are retained on the mineral. Since the ability of the proteins to inhibit hydroxyapatite formation and to bind calcium is located in the N-terminal proline-poor part, it is possible that these activities are retained after proteolytic digestion of the adsorbed proteins.
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- BARTLETT G. R. Phosphorus assay in column chromatography. J Biol Chem. 1959 Mar;234(3):466–468. [PubMed] [Google Scholar]
- Bennick A., Cannon M. Quantitative study of the interaction of salivary acidic proline-rich proteins with hydroxyapatite. Caries Res. 1978;12(3):159–169. doi: 10.1159/000260326. [DOI] [PubMed] [Google Scholar]
- Bennick A. Chemical and physical characteristics of a phosphoprotein from human parotid saliva. Biochem J. 1975 Mar;145(3):557–567. doi: 10.1042/bj1450557. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bennick A. Chemical and physical characterization of a phosphoprotein, Protein C, from human saliva and comparison with a related protein A. Biochem J. 1977 May 1;163(2):229–239. doi: 10.1042/bj1630229. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bennick A. The binding of calcium to a salivary phosphoprotein, protein A, common to human parotid and submandibular secretions. Biochem J. 1976 Apr 1;155(1):163–169. doi: 10.1042/bj1550163. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DAVIS B. J. DISC ELECTROPHORESIS. II. METHOD AND APPLICATION TO HUMAN SERUM PROTEINS. Ann N Y Acad Sci. 1964 Dec 28;121:404–427. doi: 10.1111/j.1749-6632.1964.tb14213.x. [DOI] [PubMed] [Google Scholar]
- HEILMANN J., BARROLLIER J., WATZKE E. Beitrag zur Aminosäurebestimmung auf Papierchromatogrammen. Hoppe Seylers Z Physiol Chem. 1957;309(4-6):219–220. [PubMed] [Google Scholar]
- Hay D. I. The adsorption of salivary proteins by hydroxyapatite and enamel. Arch Oral Biol. 1967 Aug;12(8):937–946. doi: 10.1016/0003-9969(67)90088-x. [DOI] [PubMed] [Google Scholar]
- Hay D. I. The interaction of human parotid salivary proteins with hydroxyapatite. Arch Oral Biol. 1973 Dec;18(12):1517–1529. doi: 10.1016/0003-9969(73)90127-1. [DOI] [PubMed] [Google Scholar]
- Kleinberg I. Biochemistry of the dental plaque. Adv Oral Biol. 1970;4:43–90. doi: 10.1016/b978-0-12-030504-9.50010-x. [DOI] [PubMed] [Google Scholar]
- Mayhall C. W. Concerning the composition and source of the acquired enamel pellicle of human teeth. Arch Oral Biol. 1970 Dec;15(12):1327–1341. doi: 10.1016/0003-9969(70)90021-x. [DOI] [PubMed] [Google Scholar]
- Wong R. S., Hofmann T., Bennick A. The complete primary structure of a proline-rich phosphoprotein from human saliva. J Biol Chem. 1979 Jun 10;254(11):4800–4808. [PubMed] [Google Scholar]
- Zahradnik R. T., Moreno E. C., Burke E. J. Effect of salivary pellicle on enamel subsurface demineralization in vitro. J Dent Res. 1976 Jul-Aug;55(4):664–670. doi: 10.1177/00220345760550042101. [DOI] [PubMed] [Google Scholar]