Bioprocess and Biosystems Engineering

, Volume 29, Issue 4, pp 241–252

Metabolic flux analysis of the sterol pathway in the yeast Saccharomyces cerevisiae

Authors

  • Judith Maczek
    • Department of Bioprocess Engineering, Institute of BiotechnologyTechnical University of Berlin
  • Stefan Junne
    • Department of Bioprocess Engineering, Institute of BiotechnologyTechnical University of Berlin
  • Peter Nowak
    • Department of Bioprocess Engineering, Institute of BiotechnologyTechnical University of Berlin
    • Department of Bioprocess Engineering, Institute of BiotechnologyTechnical University of Berlin
Original Paper

DOI: 10.1007/s00449-006-0072-1

Cite this article as:
Maczek, J., Junne, S., Nowak, P. et al. Bioprocess Biosyst Eng (2006) 29: 241. doi:10.1007/s00449-006-0072-1

Abstract

The yeast Saccharomyces cerevisiae is a useful model system for examining the biosynthesis of sterols in eukaryotic cells. To investigate underlying regulation mechanisms, a flux analysis of the ergosterol pathway was performed. A stoichiometric model was derived based on well known biochemistry of the pathway. The model was integrated in the Software COMPFlux which uses a global optimization algorithm for the estimation of intracellular fluxes. Sterol concentration patterns were determined by gas chromatography in aerobic and anaerobic batch cultivations, when the sterol metabolism was suppressed due to the absence of oxygen. In addition, the sterol concentrations were observed in a cultivation which was shifted from anaerobic to aerobic growth conditions causing the sterol pools in the cell to be filled. From time-dependent flux patterns, possible limitations in the pathway could be localized and the esterification of sterols was identified as an integral part of regulation in ergosterol biosynthesis.

Keywords

Ergosterol Saccharomyces cerevisiae Metabolic flux analysis Sterol esterification

Copyright information

© Springer-Verlag 2006