Abstract：
:Metabolic flux analysis is a useful tool to analyze cell metabolism. In this study, we report the use of a metabolic model with 34 fluxes to study the 293 cell, in order to improve its growth capacity in a DMEM/F12 medium. A batch, fed-batch with glutamine feeding, fed-batch with essential amino acids, and finally a fed-batch experiment with both essential and nonessential amino acids were compared. The fed-batch with glutamine led to a maximum cell density of 2.4x10(6) cells/ml compared to 1.8x10(6) cells/ml achieved in a batch mode. In this fed-batch with glutamine, it was also found that 2.5 mM ammonia was produced compared to the batch which had a final ammonia concentration of 1 mM. Ammonia was found to be growth inhibiting for this cell line at a concentration starting at 1 mM. During the fed-batch with glutamine, the flux analysis shows that a majority of amino acid fluxes and Kreb's cycle fluxes, except for glutamine flux, are decreased. This observation led to the conclusion that the main nutrient used is glutamine and that during the batch there is an overflow in the Kreb's cycle. Thus, a fed-batch with glutamine permits a better utilization of this nutrient. A fed-batch with essential amino acid without glutamine was also assayed in order to reduce ammonia production. The maximum cell density was increased further to 3x10(6) cells/ml and ammonia production was reduced below 1 mM. Flux analysis shows that the cells could adapt to a medium with low glutamine by increasing the amino acid fluxes toward the Kreb's cycle. Adding nonessential amino acids during this feeding strategy did not improve growth further and the nonessential amino acids accumulated in the medium.
journal_name
Metab Engjournal_title
Metabolic engineeringauthors
Nadeau I,Sabatié J,Koehl M,Perrier M,Kamen Adoi
10.1006/mben.2000.0152subject
Has Abstractpub_date
2000-10-01 00:00:00pages
277-92issue
4eissn
1096-7176issn
1096-7184pii
S1096-7176(00)90152-6journal_volume
2pub_type
杂志文章abstract：:The modularity and versatility of an engineered functional reversal of the β-oxidation cycle make it a promising platform for the synthesis of longer-chain (C≥4) products. While the pathway has recently been exploited for the production of n-alcohols and carboxylic acids, fully capitalizing on its potential for the sy...
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journal_title：Metabolic engineering
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journal_title：Metabolic engineering
pub_type： 杂志文章
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pub_type： 杂志文章,评审
doi：10.1006/mben.2000.0168
更新日期：2001-01-01 00:00:00
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journal_title：Metabolic engineering
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doi：10.1016/j.ymben.2017.03.004
更新日期：2017-05-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2013.03.001
更新日期：2013-05-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章,评审
doi：10.1016/j.ymben.2014.09.007
更新日期：2015-01-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章,评审
doi：10.1016/j.ymben.2003.10.008
更新日期：2004-01-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2016.12.008
更新日期：2017-01-01 00:00:00
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pub_type： 杂志文章
doi：10.1016/j.ymben.2018.11.009
更新日期：2019-03-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2016.12.011
更新日期：2017-01-01 00:00:00
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pub_type： 杂志文章
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pub_type： 杂志文章,评审
doi：10.1016/j.ymben.2006.01.005
更新日期：2006-07-01 00:00:00
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pub_type： 杂志文章,评审
doi：10.1016/j.ymben.2011.09.003
更新日期：2012-05-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2016.12.001
更新日期：2017-01-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2014.03.005
更新日期：2014-05-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2012.08.006
更新日期：2012-11-01 00:00:00
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doi：10.1016/j.ymben.2018.02.002
更新日期：2018-03-01 00:00:00
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journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2008.08.006
更新日期：2008-11-01 00:00:00
abstract：:(13)C metabolic flux analysis (MFA) has become an important and powerful tool for the quantitative analysis of metabolic networks in the framework of metabolic engineering. Isotopically instationary (13)C MFA under metabolic stationary conditions is a promising refinement of classical stationary MFA. It accounts for t...
journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2006.05.006
更新日期：2006-11-01 00:00:00
abstract：:Fumaric acid, a dicarboxylic acid used as a food acidulant and in manufacturing synthetic resins, can be produced from glucose in fermentation by Rhizopus oryzae. However, the fumaric acid yield is limited by the co-production of ethanol and other byproducts. To increase fumaric acid production, overexpressing endogen...
journal_title：Metabolic engineering
pub_type： 杂志文章
doi：10.1016/j.ymben.2012.07.001
更新日期：2012-09-01 00:00:00
