Polysaccharides such as starch, cellulose or hemicellulose which constitute the largest part of plant biomass are not fermentable by the yeastSaccharomyces cerevisiae. At the moment the conversion of such compounds depends on the addition of enzymes (e.g. α‐amylase, glucoamylase, xylose isomerase, endoglucanase exoglucanase and β‐glucanase) prior to fermentation. Therefore it is of great commercial interest to create new yeast strains which are able to convert polysaccharides of plant biomass directly into fermentable sugars.