Effect of extracellular glutamine concentration on primary and secondary metabolism of a murine hybridoma: An in vivo 13C nuclear magnetic resonance study
Article first published online: 26 MAR 2000
Copyright © 1998 John Wiley & Sons, Inc.
Biotechnology and Bioengineering
Volume 57, Issue 2, pages 172–186, 20 January 1998
How to Cite
Mancuso, A., Sharfstein, S. T., Fernandez, E. J., Clark, D. S. and Blanch, H. W. (1998), Effect of extracellular glutamine concentration on primary and secondary metabolism of a murine hybridoma: An in vivo 13C nuclear magnetic resonance study. Biotechnol. Bioeng., 57: 172–186. doi: 10.1002/(SICI)1097-0290(19980120)57:2<172::AID-BIT6>3.0.CO;2-K
- Issue published online: 26 MAR 2000
- Article first published online: 26 MAR 2000
- Manuscript Accepted: 21 JUN 1997
- Manuscript Received: 21 JUN 1996
- University of California Biotechnology and Education Program
- NSF PYI Award of D.S. Clark, Dow Chemical Company, Merck and Company, and Xoma Corporation
- futile cycling;
- hollow fiber bioreactor;
The effect of changes in extracellular glutamine level on metabolism of a murine hybridoma was examined with in vivo nuclear magnetic resonance (NMR) spectroscopy. Cells were cultured in a hollow-fiber bioreactor at high cell density to allow intracellular metabolite levels to be determined on a metabolically relevant time scale. Steady infusions of [1-13C] glucose were used to label glycolytic and tricarboxylic acid cycle intermediates, which permitted continuous monitoring with NMR spectroscopy during changes in environmental glutamine level. Samples of the extracellular medium were also analyzed to determine the effect of glutamine on other metabolites associated with primary and secondary metabolism. The changes in glutamine concentration had several effects on primary and secondary metabolism, depending on the rate the changes were made. For a brief reduction in feed glutamine concentration from 4 to 0 mM (which produced a rapid change from 0.67 to ∼0 mM in residual glutamine), large changes were observed in the rate of consumption of metabolites normally associated with energy production. Antibody synthesis was strongly stimulated and nitrogen metabolism was significantly altered. For a more prolonged reduction from 2.4 to 1.2 mM (which produced a slower reduction from 0.30 to 0.08 mM in residual glutamine), much smaller changes were observed even though the concentration of glutamine at the reduced feed level was very low. Energy metabolism did not appear to be limited by glutamine at 0.08 mM, which suggests that significant futile cycling may occur in energy producing pathways when excess glucose and glutamine are available. However, this concentration of extracellular glutamine appeared to affect some anabolic pathways, which require amino groups from glutamine. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng57: 172–186, 1998.