Let's call today Throwback Tuesday, and go way, way back to the 1920s.
That's when Sir Alexander Fleming stumbled on a mold that stopped bacteria from growing in a petri dish. He called it penicillin.
Ever since that huge discovery, people have been looking all over the Earth for more organisms that can fight disease.
Brian Murphy has been searching at the bottom of the Great Lakes.
He’s a medicinal chemist at the University of Illinois at Chicago, and he’s scooped up more than 600 strains of a kind of bacteria called actinomycetes from Lake Huron.
He and his team are looking for something called drug leads. That’s the first step in discovering new medicines.
"What’s special about actinomycetes is they dedicate, in some parts, up to 10% of their genome to the production of secondary metabolites – that’s just a fancy word for small molecules. And we think we can use these small molecules as drug leads," he says.
Murphy says these leads could end up becoming a new antibiotic, an anticancer agent or an antiviral agent. He says the Great Lakes are a potential gold mine.
"Very few to no people have actually explored freshwater actinomycetes as a source for potential drug leads, and that’s what we’d like to do here. We’re perfectly situated in Chicago to study a number of the different Great Lakes and the ability of the bacteria within to produce these small molecule drug leads," says Murphy.
The Centers for Disease Control and Prevention say antibiotic resistance is one of their major concerns. Brian Murphy says identifying new drug leads can help with that problem.
"Our work can help twofold. Number one, obviously, we want to discover some kind of a drug lead, something that can be brought into clinical trials and potentially be developed as an antibiotic."
But he says it’s very difficult to develop a drug: You have to get something that hits the bacteria, but that's not too toxic to humans, and you have to be able to produce enough of it.
"When we isolate a very interesting small molecule in the lab, maybe it’ll never become a drug, and that’s fine, but what we can do is we can analyze the way in which it inhibits the growth of bacteria. If this thing hits a target that we never knew was essential for a pathogen, like the bacterium that causes tuberculosis, if we can find a molecule that hits a new target there, we can learn about how the pathogen works, and the more we know about how it works, the more other researchers around the world can use that information to design better drugs," he says.