The last time a new class of antibiotics reached the market was nearly three decades ago — but that could soon change thanks to a discovery by researchers at McMaster University in Hamilton, Canada.
A team led by researcher Gerry Wright has identified a strong candidate to challenge even some of the most drug-resistant bacteria on the planet: a new molecule called lariocidin. The findings were published in the journal Nature. Wright is a professor in McMaster’s Department of Biochemistry and Biomedical Sciences and a researcher at the university’s Michael G. DeGroote Institute for Infectious Disease Research.
The discovery of the all-new class of antibiotics responds to a critical need for new antimicrobial medicines, as bacteria and other microorganisms evolve new ways to withstand existing drugs. Antimicrobial resistance (AMR) is one of the top global public health threats, according to the World Health Organization.
“Our old drugs are becoming less and less effective as bacteria become more and more resistant to them,” Wright said.
“About 4.5m people die every year due to antibiotic-resistant infections, and it’s only getting worse.”
Wright and his team found the new molecule, a lasso peptide, holds promise as an early drug lead because it attacks bacteria in a way that’s different from other antibiotics. Lariocidin binds directly to a bacterium’s protein synthesis machinery in a completely new way, inhibiting its ability to grow and survive.
“This is a new molecule with a new mode of action,” Wright said.
“It’s a big leap forward for us.”
Lariocidin is produced by a type of bacteria called Paenibacillus, which the researchers retrieved from a soil sample collected from a Hamilton backyard.
“When we figured out how this new molecule kills other bacteria, it was a breakthrough moment,” said Manoj Jangra, a postdoctoral fellow in Wright’s lab.
In addition to its unique mode of action and its activity against otherwise drug-resistant bacteria, the researchers are optimistic about lariocidin because it ticks a lot of the right boxes: it’s not toxic to human cells, it’s not susceptible to existing mechanisms of antibiotic resistance, and it also works well in an animal model of infection.
Wright and his team are now laser-focused on finding ways to modify the molecule and produce it in quantities large enough to allow for clinical development. Wright says because this new molecule is produced by bacteria — and “bacteria aren’t interested in making new drugs for us” — much time and resources are needed before lariocidin is ready for market.
“The initial discovery — the big a-ha! moment — was astounding for us, but now the real hard work begins,” Wright said.
“We’re now working on ripping this molecule apart and putting it back together again to make it a better drug candidate.”
Jim Cornall is editor of Deeptech Digest and publisher at Ayr Coastal Media. He is an award-winning writer, editor, photographer, broadcaster, designer and author. Contact Jim here.
