CBI researchers developed a way to make the sugars in plant cells more accessible for producing biofuels

Study makes plant sugars more accessible for biofuel production

Researchers collaborating through the Center for Bioenergy Innovation recently developed a way to make the sugars in plant cells more accessible for producing second-generation biofuels. The results are published in Carbohydrate Polymers.

The outer walls of plant cells are constructed from polysaccharides, molecules made of bonded sugars. These molecules determine the physical properties of plants and affect their growth. A metabolic reaction called acetylation modifies the sugar chains to support life processes like cell wall strengthening.

“You can imagine the sugar is a long chain and has all kinds of decorations like on a Christmas tree,” said researcher and first author Hsin-Tzu Wang. Acetylation is the process that adds these “decorations” – but they’re getting in the way of making a biofuel product. “The tree itself is the raw material, so we don’t want those decorations,” said Wang, who conducted the research in the lab of principal investigator Breeanna Urbanowicz. “We are modifying the proteins involved in synthesis, so there is a smaller amount of decoration.”

CBI facilitated collaboration with the National Renewal Energy Laboratory to run simulations predicting which amino acids – components of proteins – have the most important influence on acetylation of the sugar chains. In her lab, Wang tested the best candidates to draw conclusions about their functions.

She and her team were able to identify an amino acid that is key to modifying the long-chain sugar. “We can use this method in the future to adjust the protein’s activity and thus ‘change the decor on the Christmas tree’ – which will make biofuel production easier down the line,” she said.

The study’s method of combining computational analysis with benchwork can also be applied to analyzing similar proteins in other organisms and feedstocks, Wang said. The approach can guide future enzyme engineering to redesign plant cell walls without compromising plant growth or height.

In addition, Wang said, “The modified proteins we generated can be used to synthesize long-chain sugars with adjustable decoration in a cell-free system. This has applications in creating eco-friendly materials for use in drug delivery and food packaging.”

The Center for Bioenergy Innovation (CBI) at Oak Ridge National Laboratory is one of four Department of Energy Bioenergy Research Centers focused on advancing biofuels and bioproducts for a vibrant domestic bioeconomy. CBI is accelerating the development of bioenergy-relevant plants and microbes to enable production of drop-in sustainable aviation fuel, bioproducts that sequester carbon indefinitely, and sustainable replacements for plastics and other environmentally harmful products. CBI research is supported by the Biological and Environmental Research program in DOE’s Office of Science.