Abstract:
:The problems of engineering increased flux in metabolic pathways are analyzed in terms of the understanding provided by metabolic control analysis. Over-expression of a single enzyme is unlikely to be effective unless it is known to have a high flux control coefficient, which can be used as an approximate predictive tool. This is likely to rule out enzymes subject to feedback inhibition, because it transfers control downstream from the inhibited enzyme to the enzymes utilizing the feedback metabolite. Although abolishing feedback inhibition can restore flux control to an enzyme, it is also likely to cause large increases in the concentrations of metabolic intermediates. Simultaneous and coordinated over-expression of most of the enzymes in a pathway can, in principle, produce substantial flux increases without changes in metabolite levels, though technically it may be difficult to achieve. It is, however, closer to the method used by cells to change flux levels, where coordinated changes in the level of activity of pathway enzymes are the norm. Another option is to increase the demand for the pathway product, perhaps by increasing its rate of excretion or removal. Copyright 1998 John Wiley & Sons, Inc.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Fell DAdoi
10.1002/(sici)1097-0290(19980420)58:2/3<121::aid-bsubject
Has Abstractpub_date
1998-04-05 00:00:00pages
121-4issue
2-3eissn
0006-3592issn
1097-0290pii
10.1002/(SICI)1097-0290(19980420)58:2/3<121::AID-Bjournal_volume
58pub_type
杂志文章abstract::The spatial cell-material interaction remains vital issue in forming biodegradable scaffolds in Tissue Engineering. In this study, to understand the influence of spatial architecture on cellular behavior, 2D and 3D chitosan scaffolds of 50-190 kD and >310 kD MW were synthesized through air drying and controlled rate f...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20703
更新日期:2006-01-05 00:00:00
abstract::The anaerobic digestion of a cellulose-enriched fraction of domestic refuse by means of rumen microorganisms in an "artificial rumen" digester was studied. Various combinations of solid and liquid retention times and loading rates were applied to establish optimum conditions for the acidogenic phase digestion of the r...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260320604
更新日期:1988-09-05 00:00:00
abstract::A systematic, kinetic study and comparison of the leaching of mixed metal sulfides by galvanic conversion and in the presence of bacteria has been carried out for the first time using both powder (-100 to -400 mesh) and larger (bulk) specimen systems. The rates of dissolution of copper from chalcopyrite and zinc from ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260240413
更新日期:1982-04-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24815
更新日期:2013-05-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20897
更新日期:2006-10-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260420409
更新日期:1993-08-05 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
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更新日期:2007-12-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
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更新日期:1997-07-20 00:00:00
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doi:10.1002/bit.27113
更新日期:2019-11-01 00:00:00
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journal_title:Biotechnology and bioengineering
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更新日期:2013-02-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10299
更新日期:2002-08-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21813
更新日期:2008-07-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960420)50:2<222::AID-BIT
更新日期:1996-04-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260330606
更新日期:1989-02-05 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19990405)63:1<46::aid-bit5
更新日期:1999-04-05 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:2000-04-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260420506
更新日期:1993-08-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10764
更新日期:2003-10-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960820)51:4<375::AID-BIT
更新日期:1996-08-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26523
更新日期:2018-04-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260440409
更新日期:1994-08-05 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26871
更新日期:2019-04-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
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更新日期:2001-01-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10348
更新日期:2002-10-20 00:00:00
abstract::The S-System formalism provides a popular, versatile and mathematically tractable representation of metabolic pathways. At steady-state, after a logarithmic transformation, the S-System representation reduces into a system of linear equations. Thus, the maximization of a particular metabolite concentration or a flux s...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19971020)56:2<145::AID-BIT
更新日期:1997-10-20 00:00:00
abstract::Animal cell culture is widely used in biotechnology for the production of many biological products. In situ microscopes acquire images directly from cell suspensions and analyze the images in matters of cell concentration, cell size distribution and cell morphology. Their applicability was already proven for yeast and...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21523
更新日期:2008-01-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24351
更新日期:2012-03-01 00:00:00
abstract::The specific monoclonal antibody productivity (q(Mab)) of a murine hybridoma (CC9C10) increased with incubation temperature in the range 33 degrees C to 39 degrees C. q(Mab) was constant at each temperature and was independent of the phase of culture. The q(Mab) increased 97% at 39 degrees C and decreased by 21% at 33...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260441011
更新日期:1994-11-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
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更新日期:1986-11-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19970705)55:1<118::AID-BIT
更新日期:1997-07-05 00:00:00