Bioprocess and Biosystems Engineering

, Volume 30, Issue 6, pp 397–418

Metabolic flux analysis for optimizing the specific growth rate of recombinant Aspergillus niger

  • R. Gheshlaghi
  • J. M. Scharer
  • M. Moo-Young
  • P. L. Douglas
Original Paper

DOI: 10.1007/s00449-007-0136-x

Cite this article as:
Gheshlaghi, R., Scharer, J.M., Moo-Young, M. et al. Bioprocess Biosyst Eng (2007) 30: 397. doi:10.1007/s00449-007-0136-x

Abstract

A comprehensive metabolic network comprising three intracellular compartments (cytoplasm, mitochondrion and peroxisome) was developed for Aspergillus niger. The metabolic flux network includes carbohydrate and amino acid metabolism in both anabolic and catabolic reactions. Linear programming was used for the optimization of the specific growth rates in combination with 37 measured input and output fluxes of the key metabolites to evaluate corresponding intracellular flux distributions throughout the batch fermentations. Logarithmic sensitivity analysis revealed that the addition of proline, alanine and glutamate benefited growth in defined media. The experimental observations and flux analysis showed that tyrosine was a potential candidate for biomass production improvement. Model predictions was verified by conducting batch and fed-batch fermentations and it was found that the addition of the four amino acids according to the predetermined schedule resulted in a 44 and 41% improvements in biomass and recombinant protein productions, respectively.

Keywords

Aspergillus nigerHen egg white lysozymeMetabolic flux analysisLogarithmic sensitivityMetabolic pathways

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • R. Gheshlaghi
    • 1
  • J. M. Scharer
    • 1
  • M. Moo-Young
    • 1
  • P. L. Douglas
    • 1
  1. 1.Department of Chemical EngineeringUniversity of waterlooWaterlooCanada