You are here: Home
/ Publication Information
Title: Changing flux of xylose metabolites by altering expression of xylose reductase and xylitol dehydrogenase in recombinant Saccharomyces cerevisiae
Author: Jin, Yong-Su; Jeffries, Thomas W.;
Source: Applied biochemistry and biotechnology. Vol. 105-108 (2003): Pages 277-285
Publication Series: Miscellaneous Publication
Description: We changed the fluxes of xylose metabolites in recombinant Saccharomyces cerevisiae by manipulating expression of Pichia stipitis genes(XYL1 and XYL2) coding for xylose reductase (XR) and xylitol dehydrogenase (XDH), respectively. XYL1 copy number was kept constant by integrating it into the chromosome. Copy numbers of XYL2 were varied either by integrating XYL2 into the chromosome or by transforming cells with XYL2 in a multicopy vector. Genes in all three constructs were under control of the strong constitutive glyceraldehyde-3-phosphate dehydrogenase promoter. Enzymatic activity of XR and XDH in the recombinant strains increased with the copy number of XYL1 and XYL2. XR activity was not detected in the parent but was present at a nearly constant level in all of the transformants. XDH activity increased 12-fold when XYL2 was on a multicopy vector compared with when it was present in an integrated single copy. Product formation during xylose fermentation was affected by XDH activity and by aeration in recombinant S. cerevisiae. Higher XDH activity and more aeration resulted in less xylitol and more xylulose accumulation during xylose fermentation. Secretion of xylulose by strains with multicopy XYL2 and elevated XDH supports the hypothesis that D-xylulokinase limits metabolic flux in recombinant S. cerevisiae.
Keywords: Metabolic flux, metabolic engineering, xylose, xylose reductase, xylitol dehydrogenase
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
XML: View XML
Jin, Yong-Su; Jeffries, Thomas W. 2003. Changing flux of xylose metabolites by altering expression of xylose reductase and xylitol dehydrogenase in recombinant Saccharomyces cerevisiae. Applied biochemistry and biotechnology. Vol. 105-108 (2003): Pages 277-285
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility