Microbiology Program

Through the Microbiology Program, NIDCR supports basic and translational research on the role of microbes in dental health and disease. Four broad topic areas characterize the basic research portfolio funded under this program. These include: microbial ecology, polyomics, pathogenesis, and prevention and treatment strategies. Applicants are encouraged to contact the program director early in the application process to determine Institute interest prior to submission.

Microbial Ecology

The oral microbiota (composed of dentally-relevant bacteria, archaea, fungi and viruses) is one of the most diverse populations of microorganisms found anywhere in the human body. Dental infections such as caries or periodontitis are the most common infectious diseases in humans and manifest when certain microbes either take advantage of ecological changes in the mouth, changes in host defense status, or by subverting the resident commensal flora and converting to a pathogenic biofilm. Research projects relevant to this topic area include studies investigating:

  • The basic biology of oral biofilms, their formation and methods for modulation or eradication
  • How changes in host status or other ecological factors modulate the composition of the oral microbiota leading to the emergence of pathogens and/or progression of the commensal flora to a disease state
  • How microbial stress responses modify physiology and facilitate in vivo survival and persistence in the mouth
  • What role microbial cell-cell interactions and differential gene expression play in the ecology of complex communities and how this affects dental health or disease

Microbial Polyomics

Metagenomic analyses of the oral microbiota, particularly through the Human Microbiome Project (HMP) and the Human Oral Microbiome Database (HOMD) have revolutionized our understanding of this complex microbial community. Likewise, the full tool kit of current polyomic technologies (proteomics, transcriptomics, interactomics, etc.) and computational tools continue to provide an intimate view into the structure and function of oral microorganisms residing in the plaque biofilm as well as their interactions and responses to host tissues, defense mechanisms, dietary status and overall health status. They continue to elucidate previously unrecognized pathogenic mechanisms that could lead to new treatment options. In addition, data from these studies enable extensive comparisons between bacterial genera, species and strains thereby expanding our understanding of microbial systematics as well as helping to identify the genetic basis for virulence and survival in the oral cavity. Research projects relevant to this topic area include studies investigating:

  • Microbial dark matter; that category of organisms that remain uncultivable in vitro and are known only by their genomic sequences
  • New technologies and culture systems to domesticate previously uncultivable organisms so that they can be cultivated and studied in vitro
  • The role of new species, particularly the fraction that remain uncultivable, in pathogenesis, modulation of host response and collective physiology of complex microbiotas

Microbial Pathogenesis

In this topic area, projects apply the latest biochemical and polyomic technologies to identify and characterize specific microbial products or components involved in virulence and disease pathogenesis. Studies that characterize virulence factors by using, for example, in vivo expression technology and novel animal model systems that recapitulate the human oral cavity are needed, as is research on the complex interactions that occur in polymicrobial populations both above and below the gum line. Studies that delineate the biological mechanisms involved in increased susceptibility to infection via risk factors such as tobacco use and systemic co-morbidities, such as diabetes, are of high interest. Research projects relevant to this topic area include studies investigating how the microbiota:

  • Adheres to and invades host tissues
  • Initiates host cell death, growth or cytokine production
  • Induces inflammation and tissue damage
  • Leads to the release of factors that destroy host tissue
  • Modulates the host defense response system

Prevention and Treatment Strategies for Oral Infections

Dental caries and periodontitis may be prevented or treated using the principles of infectious disease. In this regard, research is needed on specific approaches to selectively reduce the pathogenic flora without altering the normal commensal population. Moreover, improvements in detection of pathogens and how to modify pathogenic mechanisms may lead to significant advances in early intervention and more effective treatments. Research projects relevant to this topic area include those investigating how:

  • The resident commensal microbiota maintains oral health and can be modulated or subverted by dental pathogens
  • Dental pre- and probiotic preparations modulate the commensal flora in order to maintain health or treat disease
  • New anti-infective treatments such as new-in-class antimicrobial compounds targeting biofilms or genetic tools such as CRISPR can be utilized to treat dental infectious diseases
Last Reviewed
July 2018