Such insights could lead to new ways of engineering bacteria to clean up environmental messes, said associate professor of chemistry E. Neil Marsh, who did the work with postdoctoral fellow Chunhua Qiao.
Free radicals---highly reactive chemical species that have been implicated in aging, diseases such as Alzheimer's and cancer, and even destruction of the ozone layer---aren't all bad, Marsh said. Many essential chemical reactions occurring in living organisms involve enzymes that use radicals. In the work described in the JACS paper, Marsh and Qiao investigated the chemical reactions that allow the bacterium Thauera aromatica to live on toluene as its sole source of carbon and energy.
"Toluene is a by-product of oil refining, so there's quite a lot of environmental contamination with this and related hydrocarbons, from refineries or chemical plants," Marsh said. "Because of their molecular structure, these compounds are very difficult to degrade, which is why they're pollution hazards." Toluene is especially worrisome because it's more soluble in water than most organic compounds are, which means that it can contaminate groundwater.
Bacteria such as T. aromatica hold promise for use in cleaning up environmental pollutants because they not only can break down hazardous chemicals, but they can also do it underground, in oxygen-scarce environments---just the sort of places where toluene could be causing problems.
Marsh would like to transfer T. aromatica's toluene-degrading abilities to other bacteria that are more easily cultured and more
Source:University of Michigan