VATIS UPDATE Article

A recent discovery by researchers at Sandia National Laboratories (SNL), the United States, may unlock the potential of biofuel waste, and ultimately make biofuels competitive with petroleum. The researchers have decoded the structure and behavior of LigM, an enzyme that breaks down molecules derived from lignin. The enzyme has little in common with other, better understood proteins, which previously made it im-possible for scientists to guess how it functions.

This is the first time anyone has solved the structure of LigM, opening a path toward new molecules and new, marketable products. Researchers knew enzymes could metabolize lignin and its derivatives because there are decades-old records of bacteria using enzymes for this purpose. Sphingomonas bacterium was discovered living in the waste water of a pulp mill more than 30 years ago.

Once researchers realized the bacterium’s unique enzymatic pathways enabled it to live on lignin, their challenge then was to understand the enzymes in these pathways so they could mimic what nature had already done, and use that understanding productively. The team focused on LigM, an enzyme used by Sphingomonas, because it performs a key step in the conversion of lignin derivatives and it is the simplest of the known enzyme systems that perform this function.