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Oral Presentation 2-06 Metabolic Engineering of Saccharomyces cerevisiae for Efficient Fermentation of Lignocellulosic Hydrolysates Lisbeth Olsson Center for Process Biotechnology Building 223 Technical University of Denmark DK-2800 Kgs Lyngby, Denmark Telephone: (45) 4525-2677; Fax: (45) 4588-4148; E-mail: lisbeth.olsson@biocentrum.dtu.dk
Utilization of potentially cheap substrates, such as
lignocellulose materials, can contribute to making bioethanol manufacturing
more competitive to fossil fuels, but the processing and utilization of this
substrate is complicated. First, the
complex polymer structures should be degraded to sugar units that can be used
by the fermentation microorganism. The
raw material composition (including both hexoses and pentoses) imposes a
requirement for an efficient fermentation process where all sugars are
metabolized. Furthermore, the
microorganism should also tolerate the conditions prevailing in lignocellulosic
hydrolysates. Sacchromyces cerevisiae has a long tradition for alcohol production. The process technology for ethanol production by S. cerevisiae is well established and S. cerevisiae has proven to be a robust and stress-tolerant microorganism. However, the substrate utilization range in S. cerevisiae is limited. Through metabolic engineering, strains have been constructed which feature restricted xylose utilization rates. On-going efforts focus on further enhancing the properties of xylose fermenting S. cerevisiae. Several approaches to improve the properties of S. cerevisiae by metabolic engineering for utilization of lignocellulosic hydrolysates will be discussed.
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