NEW SACCHAROMYCES CEREVISIAE STRAINS UTILIZING XYLOSE

摘要

A mutant strain of Saccharomyces cerevisiae which utilises xylose. The strain overexpresses xylose reductase, xylitol dehydrogenase and xylokinase. In addition, one or more genes encoding NADPH-producing enzymes and one or more genes encoding NADPH-consuming enzymes are up-regulated. A method for selecting an improved S. cerevisiae strain, which is cultivated with xylose as the only carbon source under aerobic conditions followed by microaerobic and anaerobic conditions. Each cultivation condition stretches over many generations and is followed by a selection for growth on xylose. Random mutagenesis is carried out during or after the aerobic phase.