Applied Microbiology and Biotechnology

, Volume 82, Issue 5, pp 909–919

Impact of overexpressing NADH kinase on glucose and xylose metabolism in recombinant xylose-utilizing Saccharomyces cerevisiae

  • Jin Hou
  • Goutham N. Vemuri
  • Xiaoming Bao
  • Lisbeth Olsson
Applied Microbial and Cell Physiology

DOI: 10.1007/s00253-009-1900-4

Cite this article as:
Hou, J., Vemuri, G.N., Bao, X. et al. Appl Microbiol Biotechnol (2009) 82: 909. doi:10.1007/s00253-009-1900-4

Abstract

During growth of Saccharomyces cerevisiae on glucose, the redox cofactors NADH and NADPH are predominantly involved in catabolism and biosynthesis, respectively. A deviation from the optimal level of these cofactors often results in major changes in the substrate uptake and biomass formation. However, the metabolism of xylose by recombinant S. cerevisiae carrying xylose reductase and xylitol dehydrogenase from the fungal pathway requires both NADH and NADPH and creates cofactor imbalance during growth on xylose. As one possible solution to overcoming this imbalance, the effect of overexpressing the native NADH kinase (encoded by the POS5 gene) in xylose-consuming recombinant S. cerevisiae directed either into the cytosol or to the mitochondria was evaluated. The physiology of the NADH kinase containing strains was also evaluated during growth on glucose. Overexpressing NADH kinase in the cytosol redirected carbon flow from CO2 to ethanol during aerobic growth on glucose and to ethanol and acetate during anaerobic growth on glucose. However, cytosolic NADH kinase has an opposite effect during anaerobic metabolism of xylose consumption by channeling carbon flow from ethanol to xylitol. In contrast, overexpressing NADH kinase in the mitochondria did not affect the physiology to a large extent. Overall, although NADH kinase did not increase the rate of xylose consumption, we believe that it can provide an important source of NADPH in yeast, which can be useful for metabolic engineering strategies where the redox fluxes are manipulated.

Keywords

NADH kinasePOS5Saccharomyces cerevisiaeNADPHXylose

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Jin Hou
    • 1
    • 2
  • Goutham N. Vemuri
    • 1
    • 4
  • Xiaoming Bao
    • 2
  • Lisbeth Olsson
    • 1
    • 3
  1. 1.Center for Microbial BiotechnologyTechnical University of DenmarkLyngbyDenmark
  2. 2.The State Key Laboratory of Microbial Technology, The College of Life ScienceShandong UniversityJinanPeople’s Republic of China
  3. 3.Industrial Biotechnology, Department of Chemical and Biological EngineeringChalmers University of TechnologyGothenburgSweden
  4. 4.Systems Biology, Department of Chemical and Biological EngineeringChalmers University of TechnologyGothenburgSweden