Dental plaque is a precursor of periodontal disease, one of the most common bacterial infections of man. The factors that regulate the colonization of plaque by periodontal pathogens are poorly understood. Adherence of the pathogenic bacteria to early plaque bacteria is an important first step in the colonization process. In this proposal, the adherence of Bacteroides gingivalis (a putative periodontal pathogen) to Streptococcus sanguis (an early plaque species) will be investigated. The bacteroides will be radiolabelled and binding to S. sanguis immobilized on a solid support measured. The nature of the binding will be ascertained by testing for inhibition with various physical and chemical agents. Interacting molecules will be visualized by incubating labelled organisms of one bacterial species with surface molecules extracted from its binding partner and separated by electrophoresis and blotting. The bacterial molecules involved in binding will be isolated by various chromatographic and electrophoretic techniques and/or recombinant DNA methodologies. After chemical characterization of the interacting molecules, they will be used for the production of monocional antibodies. Antibodies that inhibit binding of the homologous bacteria will be used to define the functional domains of the interacting molecules. Thus, these studies will begin to dissect the interbacterial interactions important in the colonization of the oral cavity by pathogenic organisms. This information will enhance our understanding of how periodontal pathogens establish themselves in the mouth. The elucidation of these mechanisms may allow the development of measures to prevent the colonization of these bacteria thus inhibiting the development of periodontal disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29DE009439-03
Application #
3462320
Study Section
Oral Biology and Medicine Subcommittee 1 (OBM)
Project Start
1991-08-01
Project End
1996-07-31
Budget Start
1993-08-01
Budget End
1994-07-31
Support Year
3
Fiscal Year
1993
Total Cost
Indirect Cost
Name
University of Washington
Department
Type
Schools of Dentistry
DUNS #
135646524
City
Seattle
State
WA
Country
United States
Zip Code
98195
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Lamont, R J; Hsiao, G W; Gil, S (1994) Identification of a molecule of Porphyromonas gingivalis that binds to Streptococcus gordonii. Microb Pathog 17:355-60
Cangelosi, G A; Iversen, J M; Zuo, Y et al. (1994) Oligonucleotide probes for mutans streptococci. Mol Cell Probes 8:73-80
Anderson, L C; Yang, S C; Xie, H et al. (1994) The effects of streptozotocin diabetes on salivary-mediated bacterial aggregation and adherence. Arch Oral Biol 39:261-9
Lamont, R J; Bevan, C A; Gil, S et al. (1993) Involvement of Porphyromonas gingivalis fimbriae in adherence to Streptococcus gordonii. Oral Microbiol Immunol 8:272-6
Lamont, R J; Hersey, S G; Rosan, B (1992) Characterization of the adherence of Porphyromonas gingivalis to oral streptococci. Oral Microbiol Immunol 7:193-7