Could This Enzyme Help Turn Biofuel Waste into Something Useful?

by Sarah Yang (Berkeley Lab) Joint BioEnergy Institute study targets LigM for its role in breaking down aromatic pollutants -- A protein used by common soil bacteria is providing new clues in the effort to convert aryl compounds, a common waste product from industrial and agricultural practices, into something of value.

Researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and Sandia National Laboratories working at the Joint BioEnergy Institute (JBEI) have resolved the protein structure of the enzyme LigM, which is utilized by the soil bacterium Sphingomonas to metabolize aryl compounds derived from lignin, the stiff, organic material that gives plants their structure.

Their work is reported today in the Proceedings of the National Academy of Sciences.

In biofuel production, aryl compounds are a byproduct of the breakdown of lignin. Many of the pathways leading to the breakdown of lignin involve demethylation, which is often a critical precursor to any additional steps in modifying lignin-derived aryl compounds.

Study lead author Amanda Kohler, JBEI postdoctoral researcher at Sandia, noted that LigM is an attractive demethylase for use in aromatic conversion because it is a simple, single-enzyme system. LigM is also able to maintain its functionality over a broad temperature range.

“When we’re trying to build new pathways in synthetic biology, the simpler the system the better,” said Kohler. READ MORE Abstract (Proceedings of the National Academy of Sciences)