University of California, Berkeley, researchers have taken genes from grass-eating fungi and stuffed them into yeast, creating strains that produce alcohol from tough plant material cellulose that normal yeast can't digest.
The feat could be a boon for the biofuels industry, which is struggling to make cellulosic ethanol ethanol from plant fiber, not just cornstarch or sugar economically feasible.
"By adding these genes to yeast, we have created strains that grow better on plant material than does wild yeast, which eats only glucose or sucrose," said Jamie Cate, UC Berkeley associate professor of molecular and cell biology and faculty scientist at Lawrence Berkeley National Laboratory (LBNL). "This improvement over the wild organism is a proof-of-principle that allows us to take the technology to the next level, with the goal of engineering yeast that can digest and ferment plant material in one pot."
The researchers hope to insert the same fungal genes into industrial yeast that now is used to turn sugar into ethanol biofuel in order to improve the efficiency of the fermentation process.
"The use of these cellodextrin transporters is not limited to yeast that makes ethanol," Cate said. "They could be used in any yeast that's been engineered to make, for example, other alcohols or jet fuel substitutes."
Cate and his UC Berkeley and LBNL colleagues, including first author Jonathan M. Galazka, a UC Berkeley graduate student, report their success this week in the journal Science Express. The work is funded by the Energy Biosciences Institute (EBI), a research collaboration between UC Berkeley, the University of Illinois, LBNL and the funding sponsor, BP.
Currently, the biofuel industry employs brewer's yeast, the single-celled fungus Saccharomyces cerevisiae, to convert sugar, cornstarch or other simple carbohydrates into ethanol by fermentation. But plants contain sugar polymers that yeast canno
|Contact: Robert Sanders|
University of California - Berkeley