"In the absence of protocatechuate, arginine 15 is important in the binding of PcaV to DNA in a manner that represses transcription," Sello said. "But when you introduce protocatechuate, the arginine spatially reorients to bind the compound. The accompanying conformational changes compromise the ability of the protein to bind to DNA."
An important protein
Beyond possible implications for bioenergy and sustainable chemistry, Sello says the work is meaningful for basic research in bacteriology. PcaV is a member of the MarR family of transcription factors, a family of 12,000 proteins that are known to regulate genes that influence virulence and drug resistance in other types of bacteria.
"It's a very important family of transcription factors in bacteria," Sello said. "Our paper is particularly important because it sheds light on how these proteins control gene expression and mediate responses to small molecules. While many studies of MarR family transcription factors have been published, ours is unique in the way that it synergistically integrates experimental methods from genetics, biochemistry, biophysics, and structural biology."
The research was funded by the National Science Foundation, the National Institutes of Health, and through a seed award from the Office of the Vice President of Research at Brown.
"The collegiality and size of the scientific community at Brown helps to make these collaborative, interdisciplinary research projects work," Sello said.
|Contact: Kevin Stacey|