UW-M leads work on reducing toxins for bacteria in bioprocessing

In Wisconsin, a team of investigators at the University of Wisconsin-Madison and Michigan State University have created a process for making the work environment less toxic — literally — for the organisms that do the heavy lifting in the increasingly important field of bio-products derived from cellulosic biomass.

When industrious bacteria like Saccharomyces cerevisiae, Zymomonas mobilis and Escherichia coli go to work converting the sugar in corn stover and other plant-derived materials into ethanol, they also run into aromatic compounds, which, for these particular organisms, are toxic. This slows down the conversion process, a big problem in a field that needs to economize as much as possible to compete with fossil fuels.

Researchers propose sending in a sort of microbial cleanup crew to make things safer for the glucose-eaters.

The plan relies on Rhodopseudomonas palustris, a versatile bacterium that feeds on the aromatics but isn’t interested in the sugars. This offers an advantage over currently available chemical processes for removing the aromatics, which also remove some of the valuable glucose.