The National Institutes of Health has awarded $437,250 to Narayanan Ramasubbu, PhD, of the Rutgers School of Dental Medicine to study how Aggregatibacter actinomycetemcomitans (Aa) can survive in the body. The bacterium causes periodontal disease and has been associated with heart disease.
Ramasubbu and his co-principal investigator, Mayilvahanan Shanmugam, PhD, believe that understanding how Aa thrives in the complex oral microbial world could prevent dental diseases and some types of heart diseases.
The researchers are building upon previous work on the self-produced enzyme Dispersin B, which facilitates the flight of Aa from one site to another in the mouth. But even when Aa arrives at a site with few nutrients, it manages to find a source of food.
“When there is a paucity of nutrition at an infection site, how does it get nutrition?” Ramasubbu asked.
Ramasubbu and Shanmugam believe the answer may lie in the symbiotic relationship between Aa and “good bacteria” that don’t cause illness in the oral cavity. They see evidence that the harmless bacteria produce lactate, a preferred nutrient that feeds Aa. In turn, Aa produces a glucose derivative that helps feed the beneficial bacteria.
“There’s mutual cooperation between the two,” said Ramasubbu.
A greater understanding of the dynamic could help scientists find a way to halt the microbes’ dependency on each other, cutting off the food supply for Aa and preventing infection.
“If you can establish cooperation between the two, you can find agents that stop the cooperation,” said Ramasubbu.