Removal of dental calculus remains a major consumer expense of oral health care. Products designed to inhibit supragingival calculus formation have have adverse effects on host mineral metabolism since biologic calcification occurs by similar processes in animals and bacteria. Diphosphonates and polyphosphates are partly successful since they block growth of crystals; however, they may not inhibit the initial deposition of mineral. Topical antimicrobial substances reduce the amount of plaque and delay its maturation; however, microorganisms associated with immature plaque possess the ability to calcify. This proposal investigates the potential of interfering with synthesis of calcifiable proteolipid, a protein required for initiation of calcification in oral bacteria. In Phase I the gene for Bacterionema matruchotii proteolipid will be cloned. Two strategies will be used involving precipitation of proteolipid-specific mRNA using antibodies and/or synthesis of cDNA oligomers based on the protein amino acid sequence. The genes will be used in Phase II to identify mechanisms for inhibiting proteolipid synthesis. This approach has the advantage of preventing microbial calcification without altering normal host mineralization since gene expression in eukaryotes and prokaryotes differs.
