Rather than destroying bacteria to fight infections, a University of Illinois at Chicago researcher is trying to "tweak" their savvy communication networks and block the signals that lead to infection and disease.
Researchers have known for several decades that bacteria communicate through a process called "quorum sensing," in which colonies send messages to one another to evoke responses. Many bacteria live in "biofilms," on surfaces such as catheters or medical implants, and have become increasingly resistant to antibiotics. Biofilms are coordinated by quorum sensing.
Dr. Michael Federle, assistant professor of medicinal chemistry and pharmacognosy (the study of drugs from natural products) at UIC, is trying to identify chemical and peptide inhibitors that block pheromone signaling in streptococci and which could prevent bacteria from causing infections.
Federle recently received a $500,000 grant from the Burroughs Wellcome Fund, a private biomedical research foundation, for the research. He also has a grant from the National Institutes of Health.
He hopes to develop similar inhibitor molecules that block signals and test their effectiveness in tissue culture and animal models.
"If a pathogenic bacterium uses a pheromone to turn on expression of a virulence factor (like a toxin), then maybe we can block this action with the inhibitor," Federle said, cautioning that much more research will be needed before the findings could be applied to people.
Streptococcus bugs cause strep throat, as well as meningitis, bacterial pneumonia, endocarditis and the flesh-eating bacterial condition necrotizing fasciitis.
"There's all kind of implications if we can just get a harness on bacteria in general," Federle said. "We can do some really good things as far as treatments, medicine, helping the food industry and medicines."
Developing ways to block, rather than kill, microorganisms that cause disease is important because a growing number of bacteria have found ways to avoid antibiotics, Federle explained.
"We want not to kill bacteria but actually allow them to live and survive, but not have this strong evolutionary selective pressure placed on them to find ways to resist these therapeutics," he said.
"Really, it's interfering with communities but trying to use diplomacy in a way to treat these bad bugs instead of hitting them with airstrikes and weapons," said Federle, adding he was not making a political statement.
Karen Visick, a microbiologist geneticist at the Stritch School of Medicine, Loyola University Chicago, said the research was "very nicely done and well-rounded," going from the study of basic science to potential human impact.
"It does involve an animal model, so it's not simply about asking what's happening in terms of bacteria, but whether these small molecule inhibitors would work in an animal, and that's the first step before you would go to a human," said Visick, professor of microbiology and immunology at Loyola.
"If it works, it will likely expand it to a variety of other bacteria," she said.
Bonnie Bassler, professor of molecular biology at Princeton University, said Federle was making "very original contributions" to microbiology. She noted that Federle's previous research had identified the way bacteria communicate to produce strep.
Federle did his postdoctoral training in Bassler's lab at Princeton.
"He gets that these bacteria communicate with these small molecules he discovered," said Bassler, a Howard Hughes Medical Institute investigator. "The question is, 'Has he found their Achilles' heel?'
"If he can interfere with communication between these bacteria in this important pathogen, there could be new kinds of therapeutics."Copyright © 2015, The Baltimore Sun