Genes for Xylose Fermentation, Enhanced Biofuel Production in Yeast

Efficient fermentation of cellulosic feedstocks is an essential step in the production of biofuel from plant materials. Glucose and xylose are the two most abundant monomeric carbohydrates found in hemicellulose. Saccharomyces cerevisiae, the yeast most commonly used for industrial fermentation, is able to utilize glucose but is unable to ferment xylose. However, several Ascomycete yeasts that ferment and assimilate xylose have been identified, including Pichia stipitis, whose genome has recently been sequenced.