Abstract:
:Relative levels of many individual proteins in Escherichia coli HB101 strains with 0, 37, 56, and 240 plasmids per chromosome were determined by computer image analysis of two-dimensional gel electrophoresis patterns. The plasmids investigated had very similar sequences except for small domains encoding the repressor of plasmid replication. At the intermediate plasmid copy number of 56, levels of several of the TCA cycle enzymes (oxoglutarate dehydrogenase complex, succinate thiokinase, and succinate dehydrogenase) as well as in aspartate transcarbamoylase increased. At a plasmid copy number of 240, higher amounts of PEP carboxylase as well as several of the heat shock proteins were observed. Furthermore, at high plasmid levels, significant decreases occurred in growth rate, pyruvate kinase I, pyruvate dehydrogenase complex, unadenylated glutamine synthetase, aspartate transcarbamoylase as well as in several of the proteins involved in translation. Decreases in ribosome content as well as in the free 30S and 50S ribosomal subunit pool fractions were also observed in separate analyses. These results indicate that recombinant DNA manipulations can cause major alterations in numerous host cell properties which could significantly influence cloned protein production or metabolic engineering endeavors.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Birnbaum S,Bailey JEdoi
10.1002/bit.260370808subject
Has Abstractpub_date
1991-04-05 00:00:00pages
736-45issue
8eissn
0006-3592issn
1097-0290journal_volume
37pub_type
杂志文章abstract::A new high throughput technique for enzyme characterization with specific attention to the long term stability, called "Enzyme Test Bench," is presented. The concept of the Enzyme Test Bench consists of short term enzyme tests in 96-well microtiter plates under partly extreme conditions to predict the enzyme long term...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22242
更新日期:2009-06-01 00:00:00
abstract::A mechanistically detailed single-cell model E. coli B/r-A was adapted to simulate the effects of vector presence on cell metabolism. Competition for RNA polymerase between chromosome and plasmid DNA is explicitly included. Distribution of active ribosomes among chromosome- and plasmid-derived messenger RNA, another k...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260290305
更新日期:1987-02-01 00:00:00
abstract::Bioaffinity interactions have been, and continue to be, successfully adapted from nature for use in separation and detection applications. It has been previously reported that the magnetophoretic mobility of labeled cells show a saturation type phenomenon as a function of the concentration of the free antibody-magneti...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21024
更新日期:2006-12-05 00:00:00
abstract::Transfection with polyethylenimine (PEI) was evaluated as a method for the generation of recombinant Chinese hamster ovary (CHO DG44) cell lines by direct comparison with calcium phosphate-DNA coprecipitation (CaPO4) using both green fluorescent protein (GFP) and a monoclonal antibody as reporter proteins. Following t...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21972
更新日期:2008-12-01 00:00:00
abstract::We have shown previously that a sequence-specific DNA-binding protein based on the Lac repressor protein can isolate pre-purified DNA efficiently from simple buffer solution but our attempts to purify plasmids directly from crude starting materials were disappointing with impractically low DNA yields. We have optimize...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21492
更新日期:2007-12-01 00:00:00
abstract::Bioprocess identification starts with collection of process information. Usually there is a variety of information available, consisting of actual measurement data, historical data, empirical kinetic and yield correlations, and general knowledge available from literature. A central problem is to find out how the vario...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960220)49:4<364::AID-BIT
更新日期:1996-02-20 00:00:00
abstract::Installing membranes for solid-liquid separation into biological nutrient removal (BNR) activated sludge (AS) systems makes a profound difference not only in the design of the BNR system itself, but also in the design approach for the whole wastewater treatment plant (WWTP). In multizone BNR systems with membranes in ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20311
更新日期:2005-03-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20611
更新日期:2005-08-05 00:00:00
abstract::Nitrous oxide (N2 O), a potent greenhouse gas, is reduced to N2 gas by N2 O-reducing bacteria (N2 ORB), a process which represents an N2 O sink in natural and engineered ecosystems. The N2 O sink activity by N2 ORB depends on temperature and O2 exposure, yet the specifics are not yet understood. This study explores th...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27654
更新日期:2020-12-11 00:00:00
abstract::Multiparameter flow cytometric techniques developed in our laboratories have been used for the "at-line" study of fed-batch bacterial fermentations. These fermentations were done at two scales, production (20 m(3)) and bench (5 x 10(-3) m(3)). In addition, at the bench scale, experiments were undertaken where the diff...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:2000-11-20 00:00:00
abstract::Modification of cellular functions by overexpression of genes is being increasingly practiced for tissue engineering. In the present study, we investigated whether transfection efficiency could be enhanced by magnetofection that involves the use of plasmid DNA (pDNA)/magnetite cationic liposomes (MCLs) complexes (pDNA...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21738
更新日期:2008-05-01 00:00:00
abstract::Bioartificial livers (BALs) are a potentially effective countermeasure against liver failure, particularly in cases of acute or fulminant liver failure. It is hoped these devices can sustain a patient's liver function until recovery or transplant. However, no large-scale clinical trial has yet proven that BALs are par...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22765
更新日期:2010-08-15 00:00:00
abstract::A computer-controlled headspace gas chromatograph was used to monitor the progress of ethanol production from both aerobic batch and anaerobic continuous fermentations. Using an automatic, electropneumatic sampling system, aliquots of fermentation headspace gas were injected directly onto the column for quantitative e...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260251103
更新日期:1983-11-01 00:00:00
abstract::The simultaneous biodegradation of the nonionic surfactant Tween 20 (Tw20) and pentachlorophenol (PCP) by Sphingomonas chlorophenolica sp. Strain RA2 (RA2) was measured. As a sole substrate, Tw20 biodegradation was best described by the Contois kinetic model. During concurrent biodegradation of Tw20 and PCP, the biode...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20365
更新日期:2005-03-20 00:00:00
abstract::The results from this study demonstrate that neutral resins can selectively concentrate specific indole alkaloids from dilute aqueous mixtures. Adsorption was observed to provide a one to two order of magnitude improvement in concentrating these alkaloids, as compared to an equivalent single-staged extraction. Since t...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260310905
更新日期:1988-06-05 00:00:00
abstract::D-Methionine was converted to L-methionine in a reaction system where four enzymes were used. D-amino acid oxidase (D-AAO) from Arthrobacter protophormiae was used for the complete conversion of D-methionine to 2-oxo-4-methylthiobutyric acid. Catalase was added to prevent 2-oxo-4-methylthiobutyric acid decarboxylation...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21501
更新日期:2007-12-01 00:00:00
abstract::Rifamycin B is an important polyketide antibiotic used in the treatment of tuberculosis and leprosy. We present results on medium optimization for Rifamycin B production via a barbital insensitive mutant strain of Amycolatopsis mediterranei S699. Machine-learning approaches such as Genetic algorithm (GA), Neighborhood...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20056
更新日期:2004-04-20 00:00:00
abstract::For clinical trials, large amounts of high-titer retroviral supernatants are required. However, retroviral concentration is relatively low compared with other viral vectors. Moreover, less than half of retroviral vectors suspended in a collected supernatant are infectious because of their short half-lives. In this stu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20435
更新日期:2005-05-05 00:00:00
abstract::A gene for ethionine resistance isolated from the yeast Saccharomyces cerevisiae DKD-5D-H conferred on the yeast cells resistance to seleno-L-methionine and capability to produce S-adenosyl-L-methionine in the cells. An enzymatic study of the L-methionine synthetic pathway of L-methionine proto- and auxotrophs and in ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260351107
更新日期:1990-05-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20738
更新日期:2006-03-05 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20120
更新日期:2004-08-05 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260210412
更新日期:1979-04-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19980105)57:1<71::aid-bit9
更新日期:1998-01-05 00:00:00
abstract::Myristic acid esterification has been performed by an immobilized lipase from Mucor Miehei both in n-hexane and in supercritical carbon dioxide (SCCO(2)). The enzyme is stable in SCCO(2) at 15 MPa and 323 K. The reaction rate is influenced by the concentration of water and by the reaction medium composition. A reactio...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260400218
更新日期:1992-06-20 00:00:00
abstract::Linear relations among net conversion rates of primary metabolites in fermentation processes can be determined by using the macroscopic or pathway balancing methods. It is shown that the process observability can be improved by incorporating both the abiotic proton balance and the pH control reagent addition rate meas...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19961220)52:6<713::AID-BIT
更新日期:1996-12-20 00:00:00
abstract::A novel strategy for the maximum production of a biodegradable copolymer, poly(3-hydroxybutyric-co-hydroxyvaleric) acid, P(HB-co-HV), was developed, based on the kinetic parameters obtained from fed-batch culture experiments of Alcaligenes eutrophus. The effects of various culture conditions such as mole ratio of carb...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:1999-03-05 00:00:00
abstract::A novel fed-batch approach for the production of L-phenylalanine (L-Phe) with recombinant E. coli is presented concerning the on-line control of the key fermentation parameters glucose and tyrosine. Two different production strains possessing either the tyrosine feedback resistant aroF(fbr) (encoding tyrosine feedback...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10428
更新日期:2002-12-30 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 传,古典文章,历史文章,杂志文章
doi:10.1002/(sici)1097-0290(20000320)67:6<691::aid-bit
更新日期:2000-03-20 00:00:00
abstract::Engineered human T-cells are a promising therapeutic modality for cancer immunotherapy. T-cells expressing chimeric antigen receptors combined with additional genes to enhance T-cell proliferation, survival, or tumor targeting may further improve efficacy but require multiple stable gene transfer events. Methods are t...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25538
更新日期:2015-07-01 00:00:00
abstract::The kinetics of precipitation of soya protein has been examined in a tubular flow reactor with the precipitants, ammonium sulfate, ethanol, divalent calcium, and sulfuric acid. The precipitate growth profiles obtained in all cases showed the rapid formation of a precipitate phase and the attainment of a final size wit...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280312
更新日期:1986-03-01 00:00:00