The Powe award provides seed money of $5,000 to faculty members who are in the first two years of their tenure track as an investment in promising achievements in an important area. The institution matches the award.
Much like a legislative body, some bacteria need a quorum, the presence of a critical number of individuals, before they can engage in particular activities. Typically these are activities that are only productive when carried out in unison by a community of bacteria.
The example often given is bioluminescence. Scientists noticed that once a population or colony of particular bacteria reached a certain size, the colony began to emit light. "Now many people realize that other important activities also depend upon a quorum, such as biofilm formation, releasing toxins, or becoming a virulent invader," said Rahul Kulkarni. While Kulkarni works with Vibrio cholerae as a model bacteria, quorum sensing appears to be a universal process in bacteria. So what he learns about the communication process known as quorum sensing could one day help scientists prevent a broad range of diseases caused by bacteria that are human pathogens.
How do bacteria know how many are present? Each bacterium releases a small molecule, called an autoinducer. Each bacterium also has receptors ?proteins on its cell surface -- to sense autoinducers. As the amount of autoinducer reaches a critical level, the bacteria know they have a quorum because a change is initiated in the receptor protein, which then causes a series of further changes within each bacterium.
Kulkarni is looking at the net