Visar resultat 1 - 5 av 89 avhandlingar innehållade ordet Xylose.
1. The GRE3 encoded aldo-keto reductase and its influence on xylose fermentation in recombinant Saccharomyces cerevisiae strains
Sammanfattning : The aim of the work presented in this thesis was to improve ethanol formation from xylose in recombinant Saccharomyces cerevisiae strains. This was achieved by decreasing the xylitol by-product formation. Gre3p is the major xylose-reducing enzyme in S. cerevisiae. LÄS MER
Sammanfattning : The aim of the thesis is to improve the initial steps of xylose metabolism in recombinant Saccharomyces cerevisiae. S. cerevisiae takes up xylose of poor affinity by means of hexose transporters. Metabolic control analysis was used to investigate whether the low xylose utilisation rate is due to inefficient transport. LÄS MER
Sammanfattning : Saccharomyces cerevisiae ferments hexoses in lignocellulosic hydrolysates under anaerobic conditions with high rates and ethanol yields. However, S. cerevisiae is naturally unable to utilize the pentose fraction of the hydrolysates. Xylose is the most abundant pentose sugar, and although recombinant S. LÄS MER
Sammanfattning : In metabolically engineered Saccharomyces cerevisiae expressing Pichia stipitis XYL1 and XYL2 genes, encoding xylose reductase (XR) and xylitol dehydrogenase (XDH), respectively, xylitol is excreted as the major product during anaerobic xylose fermentation and only low yields of ethanol are produced. This has been interpreted as a result of the dual cofactor dependence of XR and the exclusive use of NAD+ by XDH. LÄS MER
Sammanfattning : Baker’s yeast, Saccharomyces cerevisae, has been engineered to utilize the pentose sugar xylose present in lignocellulose biomass for the production of ethanol. Currently ethanol production from xylose is slow which limits the implementation of said strains in industrial production. LÄS MER