Scientists at UT Southwestern Medical Center have found a potential new way to stop the bacteria that cause gastroenteritis, tularemia, and severe diarrhea from making people sick. The researchers found that the molecule LED209 interferes with the biochemical signals that cause bacteria in our bodies to release toxins.
“What we have here is a completely novel approach to combating illness,” said Dr. Vanessa Sperandio, associate professor of microbiology and biochemistry at UT Southwestern and senior author of a study available online and in a future issue of Science.
Though many antimicrobial drugs are already available, new ones are needed to combat the increasing microbial resistance to antibiotics. In addition, treating some bacterial infections with conventional antibiotics can cause the release of more toxins and may worsen disease outcome.
Scientists have known for decades that millions of potentially harmful bacteria exist in the human body, awaiting a signal that it’s time to release their toxins. Without those signals, the bacteria pass through the digestive tract without infecting cells. What hasn’t been identified is how to prevent the release of those toxins, a process that involves activating virulence genes in the bacteria.
In the new study, UT Southwestern researchers describe how LED209 blocks the bacterial receptor for these signals. In 2006, the UT Southwestern researchers were the first to identify the receptor QseC sensor kinase, which is found in the membrane of a diarrhea-causing strain of Escherichia coli. This receptor receives signals from human flora and hormones in the intestine that cause the bacteria to initiate infection.
Release date: August 21, 2008
Source: UT Southwestern Medical Center
Filed Under: Drug Discovery
