BP has a long way to go before it can redeem itself from last spring's oil disaster, but helping to wean the planet off the sticky black stuff is a start. The oil giant recently teamed up with the University of Illinois, Lawrence Berkeley National Laboratory, the University of California at Berkeley, and Seoul National University to engineer a new strain of yeast that can ferment two types of sugar at the same time to produce ethanol.
Translation: the scientists have created a supercharged yeast that can gobble up sugar faster and more efficiently than any other yeast.
Glucose is generally easy to ferment—it's a primary sugar in plants—but xylose (a secondary sugar in plant stems and leaves) has historically been more difficult for yeast strains to ferment. The engineered yeast, a strain of Saccharomyces cerevisiae (common industrial yeast), can co-ferment glucose and xylose as quickly as it can ferment either sugar by itself, according to Green Car Congress. It can also convert xylose to ethanol up to 20% more efficiently than other strains.
This approach, initially developed by co-corresponding author Jamie Cate at the Lawrence Berkeley National Laboratory and the University of California at Berkeley, eliminates the costly step of adding a cellobiose-degrading enzyme to the lignocellulose mixture before the yeast consumes it. It has the added advantage of circumventing the yeast's own preference for glucose. Because the glucose can now "sneak" into the yeast in the form of cellobiose, the glucose transporters can focus on drawing xylose into the cell instead.
In practical terms, this means that ethanol could become cheaper and easier to produce. And with increasingly tense debates over the merits of government ethanol subsidies in the U.S., the industry needs all the help it can get.