Scientists testing the purple bacteria that form mats in Lake Huron sinkholes found anti-cancer and antibiotic properties. Photo: Thunder Bay Sinkholes 2008
By Sarah Coefield
coefield@msu.edu
Great Lakes Echo
July 16, 2009
The colorful cyanobacteria coating the sinkholes in Lake Huron may be ancient, but researchers are hoping they will provide new medicines for cancer and infection treatments.
Cyanobacteria produce a plethora of complex molecules. Researchers at the National Oceanic and Atmospheric Administration asked Dave Sherman to take a look at the bacteria to see if he could find any hints of medical applications.
He did.
Sherman, the Hans W. Vahlteich Professor in the Life Sciences Institute in the department of Medicinal Chemistry at the University of Michigan, studies chemicals produced by microbial organisms and looks for molecules that can fight cancer and infection.
Bacteria have long been pharmaceutical goldmines. Many of today’s modern medicines, including the popular antibiotics tetracycline and erythromycin, come from soil-dwelling bacteria.
Sherman prefers to look for drug leads in the water.
Dave Sherman
“We’re particularly interested in marine and aquatic organisms because they’ve really been understudied over the years,” he said. After seeing video of the Lake Huron sinkholes, Sherman jumped at the chance to study the unique ecosystem’s bacteria.
“It was really fantastic footage,” he said. “I was interested, because anyone who brings a new cyanobacteria to me, of course I’m interested in that.”
The novelty of new cyanobacteria so close to home was a bonus for Sherman, who generally works with samples from tropical waters. “To have a local source of some interesting biodiversity and chemical diversity is very exciting,” he said.
In 2008, Sherman began testing samples from the cyanobacteria mats and sinkhole sediments for bacteria with anti-cancer and antibiotic properties. He’s had hits in both categories. That came as no surprise to Sherman, who has studied cyanobacteria for several years.
“Cyanobacteria are really amazing organic chemists,” Sherman said. “Their biochemical characteristics are really unique. We think it’s because they’re such old organisms — they evolved over billions of years to do interesting things.”
Sherman’s next step is to pinpoint the molecules responsible for the hits in the lab and then figure out how the bacteria produce them.
“When we understand these things it gives us the opportunity to actually use methods to engineer molecules that could become drugs,” he said.
In the next six months Sherman hopes to identify a molecule that shows promise against anthrax causing bacteria. Anthrax is a dangerous disease that can be deadly if left untreated. The disease came to national attention in 2001 when letters with anthrax spores were mailed to media offices and two senators.