Great Lakes Soil Probed for Helpful Fungi
MILWAUKEE A biologist from the University of Wisconsin-Milwaukee is scouring the bottom of Lake Michigan, looking not for clams, but for bacteria and fungi that develop anti-bacterial chemicals that could be developed into life-saving drugs for humans.
Biologist Yi-Qiang Cheng and a graduate student, Melissa Barman, say the soils of the Great Lakes might harbor an untapped pharmacy -- a trove of new drug agents that could be developed into antibiotics, cancer drugs and fungus fighters.
They have identified novel strains of bacteria and fungi that appear to hold medical promise. But they add it's still too early to say how lucrative the lakes might be.
"People have been looking in every conceivable exotic environment" for biological agents, Cheng said. "I figured that since we were here, just a few blocks from Lake Michigan, we should look there."
Cheng and Barman's proximity to the lake could help with creating a natural environment for microbes, which often fail to produce their unique chemicals in laboratory settings.
The team is also employing a process called metagenomics, which allows them to identify every snippet of DNA in a sample -- enabling the team to see critters that would ordinarily die, or remain invisible, in a regular lab.
There are limitations to the technique, he said. For instance, what his computer tells him is a novel species actually might be a loose strand of DNA from another microbe, thereby over-estimating their diversity.
The team has tough slogging in the area of new antibiotics. They must prove the agents they identify are new and get pharmaceutical companies interested in developing them.
According to Steven Projan, assistant vice president for protein technologies at global pharmaceutical firm Wyeth, only seven new anti-bacterial drugs have been approved since 1998.
In 2004, of 290 drugs that major pharmaceutical companies were developing, only four were antibiotics.
Cost is a major factor, said Projan. But there's also concern that despite nearly two decades of intensive screening for new antibiotics, few novel agents have been found.
While some say this problem is insurmountable -- that the millions of bacteria and microbes on the planet share just a few dozen chemical weapons, and no more will be found -- others say the dearth of new agents is because of the outdated way researchers have been looking for them.
"Soil microbes offer an extraordinarily rich source of active compounds," said Jo Handelsman, a plant pathologist at the University of Wisconsin-Madison. "I'm just not convinced we have screened as many environments as we say we have."
"It's kind of like looking for a needle in a haystack," said Cheng. "But if you don't try, you're not going to find anything."
Source: Associated Press