Biologists from the University of Illinois have pinpointed how one bacterium, Prevotella bryantii, does it. Publishing their work in the Journal of Biological Chemistry, they suggest their findings could provide insight on livestock health, human digestion and biofuel production.
By sequencing its DNA and RNA, the researchers were able to decipher which enzymes the rumen bacterium uses to degrade xylan. Xylan is a type of hemicellulose, which is a tight network of bonded sugar molecules that helps comprise tough cell walls of plants and some algae. The enzymes convert xylan into xylose, a simple sugar.
The ethanol and butanol industries already use microbes to ferment simple sugars into fuels, but producing cellulosic biofuels has been more problematic. According to the researchers, the enzyme recipe enlisted by P. bryantii might unlock more promise for heartier feedstocks, such as switchgrass, miscanthus, and the stalks and leaves of corn.
To my knowledge, this was the first time that anyone has systematically demonstrated the deconstruction of the plant cell wall hemicellulose.
U of I’s research has created an enzyme cocktail that can release simple sugars from hemicellulose and in turn, help the biofuels industry progress.
Commercial use of this particular enzyme concoction may not be for a while, but in the meantime, the researchers plan to examine how two other rumen bacteria break down cellulose and hemicellulose.