Pathogens in biofilms are more resistant to harsh environmental stresses such as antibiotics and the host immune system. Prevention of biofilm formation is critical to advancing therapeutic treatments against infectious diseases. Oral biofilm is important for periodontal diseases in which pioneers provide substrates allowing colonization of subsequent pathogens. Oral bacterial interactions, especially coaggregation between pioneering colonizers (such as mitis group streptococci, MGS) and pathogenic species (such as Porphyromonas gingivalis or Fusobacterium nucleatum), are important for periodontal diseases. We have identified a Streptococcus sanguinis two-component system (TCS) gene that is responsible for increased adherence with P. gingivalis and F. nucleatum. We propose an integrative study of this TCS regulon and related gene functions by systems biology. To characterize the TCS regulon, the gene expression profiles will be examined using microarray technology. The DNA binding sites will be identified by ChIP-seq. To examine gene functions in biofilm, the TCS regulated gene mutants will be collected from a comprehensive gene mutant library. Bacterial interaction of these mutants with oral pathogens will be systematically examined to identify biofilm genes by confocal microscopy. The biological functions of these genes will be studied as a whole to understand the relationship of the TCS and the biofilm genes.

Public Health Relevance

Oral biofilms are important for periodontal diseases. Pathogens in biofilms are more resistant to harsh environmental stresses and clinical treatments. We propose an integrative study of streptococcal biofilm genes to advance therapy against infectious diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
1R01DE023078-01A1
Application #
8554964
Study Section
Oral, Dental and Craniofacial Sciences Study Section (ODCS)
Program Officer
Lunsford, Dwayne
Project Start
2013-07-05
Project End
2018-05-31
Budget Start
2013-07-05
Budget End
2014-05-31
Support Year
1
Fiscal Year
2013
Total Cost
$381,250
Indirect Cost
$131,250
Name
Virginia Commonwealth University
Department
Dentistry
Type
Schools of Dentistry
DUNS #
105300446
City
Richmond
State
VA
Country
United States
Zip Code
23298
Xu, Ping; Gunsolley, John (2014) Application of metagenomics in understanding oral health and disease. Virulence 5:424-32
Evans, Karra; Stone, Victoria; Chen, Lei et al. (2014) Systematic study of genes influencing cellular chain length in Streptococcus sanguinis. Microbiology 160:307-15