For the very first time, study describes a signaling pathway that affects communication between Streptococcus bacteria cells. The communication process called quorum sensing detailed in the study is published in the Journal of Biological Chemistry.
This type of bacterium is responsible for illnesses like strep throat, scarlet fever, and some cases of soft tissue infections and pneumonia. In extreme cases, or when bacteria become resistant to antibiotics, these common but serious infections can lead to death.
The University of Illinois at Chicago researchers who wrote the paper have been studying Streptococcus bacteria and have hypothesized that quorum sensing pathways are ideal drug targets for manipulating bacterial activity and suppressing virulence.
That is why Federle and his team have developed a tool to help study the quorum sensing signaling pathways. Their technology allows them to easily monitor specific gene activities and whether chemicals or other conditions affect gene expression.
Using this technique, the UIC scientists have unlocked part of the communication process and identified a small molecule that promotes quorum sensing in Streptococci. This molecule stabilizes the chemical signal -- called a pheromone -- transmitted between cells. More specifically, the compound works by blocking the enzyme that would otherwise degrade the pheromone before it can deliver a message, thus promoting its ability to act as a signal.
"We identified a molecule that disrupts inhibition of signaling," said Federle, associate professor of medicinal chemistry and pharmacognosy in the UIC College of Pharmacy. "Now that we identified this pathway and this chemical compound, we can look further for ways to manipulate quorum sensing and even silence the communication between cells."
By silencing this communication, Federle says, it might be possible "to convince bacteria to remain in a non-hostile state," something he considers vital in the face of rising antibiotic resistance in society.
"We're losing the war with bacteria," he said. "Every antibiotic we've come up with has some level of resistance in nature. We need a way to stop bacteria before they become a threat and require treatment."
Federle says this is analogous to finding a diplomatic solution or mediating a conflict before it causes harm.