This project will examine global protein expression changes in oral microbial communities and the community response to model host cells. We will select as model organisms the periodontal pathogen P. gingivalis, along with F. nucleatum and S. gordonii as representative of organism commonly found in dental biofilms and capable of synergistic interactions with P. gingivalis. In addition to differential protein expression as these organisms assemble into communities, we will also determine changes in protein expression induced by contact with gingival epithelial cells. The long-term goals of the study involve improving our fundamental understanding at the molecular level of events surrounding heterotypic oral biofilm formation and the interaction of these biofilms with host cells.
Specific Aim 1 defines reference proteomes of P. gingivalis, S. gordonii, and F. nucleatum individually, pairwise and all together. This will include global protein modification analysis using data mining techniques, and a chemical approach to global phosphorylation specifically. We will define protein relative abundance changes (relative to the single organism in isolation) that can be attributed to community microbial interactions. We will thus establish the proteome of the P. gingivalis-F. nucleatum-S. gordonii community, and the differential responses to community development in comparison to individual proteomes.
Specific Aim 2 will define the effects of gingival epithelial cells on the P. gingivalis-F. nucleatum-S. gordonii community. This will involve running the same experiments as in Aim 1, but in the presence of epithelial cells, also with comparative posttranslational modification (PTM) analysis on the microbial side. This will define the response of the community to the presence of host cells. As in Aim 1, this includes mining the datasets globally for PTMs for all known modifications using computational approaches, and in addition using a chemically based experimental approach to measuring differential global phosphorylation.
In Aim 3 we will prioritize the regulated proteins identified in Aims 1 and 2, as discovery warrants, for additional corroboration and for construction of mutants in the corresponding genes. The phenotype of the mutants in community development and responses to epithelial cells will further elucidate functional meaning and biological relevance.

Public Health Relevance

Periodontal, or gum, diseases are the major cause of tooth loss in developed countries and result from the concerted activities of groups of microorganisms. These organisms adjust expression of their proteins as they assemble into communities and interact with host cells. We will define these protein expression changes and assess their importance for contribution to the disease process. Gaining an improved understanding of protein changes is a basic requirement for improved therapeutic and diagnostic strategies.

National Institute of Health (NIH)
Research Project (R01)
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Special Emphasis Panel (ZRG1)
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Lunsford, Dwayne
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University of Washington
Engineering (All Types)
Biomed Engr/Col Engr/Engr Sta
United States
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Wright, C J; Burns, L H; Jack, A A et al. (2013) Microbial interactions in building of communities. Mol Oral Microbiol 28:83-101
Hirano, T; Beck, D A C; Wright, C J et al. (2013) Regulon controlled by the GppX hybrid two component system in Porphyromonas gingivalis. Mol Oral Microbiol 28:70-81
Kuboniwa, Masae; Hendrickson, Erik L; Xia, Qiangwei et al. (2009) Proteomics of Porphyromonas gingivalis within a model oral microbial community. BMC Microbiol 9:98
Hackett, Murray (2008) Science, marketing and wishful thinking in quantitative proteomics. Proteomics 8:4618-23
Hendrickson, E L; Lamont, R J; Hackett, M (2008) Tools for interpreting large-scale protein profiling in microbiology. J Dent Res 87:1004-15
Xia, Qiangwei; Hendrickson, Erik L; Wang, Tiansong et al. (2007) Protein abundance ratios for global studies of prokaryotes. Proteomics 7:2904-19
Xia, Qiangwei; Wang, Tiansong; Park, Yoonsuk et al. (2007) Differential quantitative proteomics of Porphyromonas gingivalis by linear ion trap mass spectrometry: non-label methods comparison, q-values and LOWESS curve fitting. Int J Mass Spectrom 259:105-116
Xia, Qiangwei; Wang, Tiansong; Taub, Fred et al. (2007) Quantitative proteomics of intracellular Porphyromonas gingivalis. Proteomics 7:4323-37
Li, Qunhua; Xia, Qiangwei; Wang, Tiansong et al. (2006) Analysis of the stochastic variation in LTQ single scan mass spectra. Rapid Commun Mass Spectrom 20:1551-7
Hendrickson, Erik L; Xia, Qiangwei; Wang, Tiansong et al. (2006) Comparison of spectral counting and metabolic stable isotope labeling for use with quantitative microbial proteomics. Analyst 131:1335-41

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