In the early 1960s, a drug-resistant cholera pandemic broke out for the seventh time in history, afflicting millions and killing hundreds of thousands every year since.
Over the past five decades, scientists have struggled to determine how V. cholerae, the bacteria associated with cholera, resists all human immune responses. But, thanks to UT biologists, the mystery is now solved.
Stephen Trent, UT associate professor of molecular genetics and microbiology, and his research team have shed light on the bacteria’s resistance mechanisms, which could pave the way for more effective antibiotics.
“We are trying to figure out how the bacteria resists the innate immune systems of humans,” says Trent, lead researcher on the study, “and use that information to engineer better treatments and therapies, which include antibiotics and vaccines.”
Cholera, which occurs predominantly in developing countries with a lack of clean water, causes profuse diarrhea and vomiting. After a devastating earthquake struck Haiti in 2010, cholera ran rampant due to contaminated water sources. Those who didn’t receive treatment within 24 hours often died from severe hydration.
The latest strain of the disease, known as El Tor, has developed a resistance to antimicrobial peptides. Found in the body, these proteins attach to the outside of the bacteria’s shell of armor, disable its defenses, and kill it.
“What we figured out is why has the new Vibrio cholera, the one that is causing the current pandemic, built resistance to the peptides,” Trent says. “And the fact that it’s resistant could begin to help us figure out why it has survived better in the human population.”
This knowledge will help scientists to eliminate resistant chromosomes and enable them to create new, more effective vaccines.
“By understanding how bacteria resist the immune systems of humans and the human hosts,” Trent says, “it helps us figure out how to make new treatments.”
Trent’s research is featured in this month’s Proceedings of the National Academy of Sciences.
A scanning electron micrograph of V. cholerae bacteria. Photo courtesy Stephen Trent.