Abstract:
:The fim inversion system of Escherichia coli (E. coli) can behave as a unidirectional switch in an efficient manner. We have developed a new expression system for E. coli, comprising the arabinose-inducible fimE gene and the fim invertible DNA segment containing a constitutively active promoter. In this system, the target gene is cloned with the promoter in the OFF orientation, resulting in no transcribed product. When induced by arabinose, the active promoter is switched to the ON orientation via FimE-catalyzed DNA inversion, and the gene is expressed. Our expression system exhibited very tightly controlled basal expression and high induced expression, with simple induction by inexpensive arabinose. These characteristics make our system suitable for large-scale expression or for production of toxic proteins.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Ham TS,Lee SK,Keasling JD,Arkin APdoi
10.1002/bit.20916subject
Has Abstractpub_date
2006-05-05 00:00:00pages
1-4issue
1eissn
0006-3592issn
1097-0290journal_volume
94pub_type
杂志文章abstract::The engineering of production cell lines to express anti-apoptotic genes has been pursued in recent years due to potential process benefits, including enhanced cell survival, increased protein expression, and improved product quality. In this study, a baby hamster kidney cell line secreting recombinant factor VIII (BH...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21479
更新日期:2007-11-01 00:00:00
abstract::The DeltaSf of one unit carbon formula weight of Escherichia coli K-12 cells, when grown on succinic acid, was calculated to be -80.13 J/deg. This value could then be used to calculate the entropy change accompanying the anabolism and metabolism of succinic acid to be 30.82 J/deg and 32.40 J/mol deg, respectively. The...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260410405
更新日期:1993-02-20 00:00:00
abstract::Lipase from Pseudomonas fluorescens biotype I was immobilized by adsorption of anion exchange resin using glutaraldehyde to enhance the adsorption. The activity yield of the immobilized lipase was very low (below 1%) when lipase activity was measured using emulsion substrate. The activity yield was 10-70% when lipase ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260360609
更新日期:1990-09-01 00:00:00
abstract::A semimechanistic multi-reaction kinetic model was developed to describe the enzymatic hydrolysis of a lignocellulosic biomass, creeping wild ryegrass (CWR; Leymus triticoides). This model incorporated one homogeneous reaction of cellobiose-to-glucose and two heterogeneous reactions of cellulose-to-cellobiose and cell...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22197
更新日期:2009-04-15 00:00:00
abstract::Membrane adsorbers may be a viable alternative to the packed-bed chromatography for clearance of virus, host cell proteins, DNA, and other trace impurities. However, incorporation of membrane adsorbers into manufacturing processes has been slow due to the significant cost associated with obtaining regulatory approval ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24720
更新日期:2013-02-01 00:00:00
abstract::The feasibility of continuous ester synthesis in a membrane bioreactor (MBR) by a recombinant cutinase from Fusarium solani pisi was investigated, using the optimal conditions previously attained by medium engineering. The objective was to analyze the MBR behavior as a differential or an integral reactor. The main com...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20010120)72:2<127::aid-bit1>3.0.
更新日期:2001-01-20 00:00:00
abstract::The downstream processing of virus particles for vaccination or gene therapy is becoming a critical bottleneck as upstream titers keep improving. Moreover, the growing pressure to develop cost-efficient processes has brought forward new downstream trains. This review aims at analyzing the state-of-the-art in viral dow...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.25545
更新日期:2015-05-01 00:00:00
abstract::The microfluidic environment provided by implanted prostheses has a decisive influence on the viability, proliferation and differentiation of cells. In bone tissue engineering, for instance, experiments have confirmed that a certain level of wall shear stress (WSS) is more advantageous to osteoblastic differentiation....
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22842
更新日期:2010-11-01 00:00:00
abstract::There are a series of examples in which phenols appear as contaminants in process streams and their selective removal is required for waste minimization. For the selective removal of a phenol from a mixture, we are exploiting the substrate specificity of the enzyme tyrosinase to convert phenols into reactive o-quinone...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960705)51:1<79::AID-BIT9
更新日期:1996-07-05 00:00:00
abstract::The characteristics of horseradish peroxidase (HRP) immobilized onto Sepharose by a photochemical-initiated graft copolymerization are presented. Active copolymers were synthesized using different amounts of glycidylmethacrylate (GMA), bisacryloylpiperazine (BAP), or 1,3,5-hexhydrotriacryloyl-(s)-triazine (HTsT) as fu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260250310
更新日期:1983-03-01 00:00:00
abstract::The copolymerization method of immobilization was used to obtain preparations of enzymes covalently incorporated in polyacrylamide gel. They possess properties making them suitable for practical use. First, the preparations are hundreds of times more stable against irreversible thermoinactivation than native enzymes. ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260250804
更新日期:1983-08-01 00:00:00
abstract::Dihydrofolate reductase (DHFR) system is used to amplify the product gene to multiple copies in Chinese Hamster Ovary (CHO) cells for generating cell lines which produce the recombinant protein at high levels. The physiological changes accompanying the transformation of the non-protein secreting host cells to a high p...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25117
更新日期:2014-03-01 00:00:00
abstract::Enzyme engineering is a powerful tool to fine-tune the enzymes. It is a technique by which the stability, activity, and specificity of the enzymes can be altered. The characteristic properties of an enzyme can be amended by immobilization and protein engineering. Among them, protein engineering is the most promising, ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.27329
更新日期:2020-06-01 00:00:00
abstract::In a stirred culture of hybridoma cells, the effects of serum reduction from 2.5% to 0% on growth and monoclonal antibody production have been investigated. The shear sensitivity of cells from the same culture has been tested in a bubble column. Serum reduction does not greatly affect viable-cell concentrations, but c...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260400125
更新日期:1992-06-05 00:00:00
abstract::Tissue engineering devices as in vitro cell culture systems in scaffolds has encountered the bottleneck due to their much lower cell functions than real tissues/organs in vivo. Such situation has been improved in some extent by mimicking the cell microenvironments in vivo from either chemical or physical ways. However...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24874
更新日期:2013-08-01 00:00:00
abstract::The production of beta-galactosidase from the E. coli phoA-lacZ fusion gene was studied to compare the gene expression behavior of two cloning methods: insertion to multicopy plasmids and integration into host cell's chromosome. The chromosome-integrating strain showed more tight control of fusion gene expression leve...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260361104
更新日期:1990-12-20 00:00:00
abstract::An unadapted mixed methanogenic sludge transformed formaldehyde into methanol and formate. The methanol to formate ratio obtained was 1:1. Formaldehyde conversion proceeded without any lag phase, suggesting the constitutive character of the formaldehyde conversion enzymes involved. Because the rate of formaldehyde con...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10294
更新日期:2002-08-05 00:00:00
abstract::Trichoplusia ni larvae were infected with baculoviruses containing genes for the expression of ultraviolet optimized green fluorescent protein (GFPuv) and several product proteins. A GFP-specific optical probe was used to both excite the green fluorescent protein (lambda(ex) = 385 nm), and subsequently monitor fluores...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10668
更新日期:2003-07-20 00:00:00
abstract::Globally, approximately a billion patients are estimated to suffer from neurological disorders. Although there are many therapeutic candidates for the central nervous system, treatment of brain disorders is restricted by the blood-brain barrier (BBB), which is a highly selective membrane that protects the brain from e...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26742
更新日期:2018-10-01 00:00:00
abstract::A technology has been developed to achieve optimal attachment of adhesion-independent lymphocytes to microcarrier beads. The activation of T-lymphocytes by concanavalin A was tested under microgravity conditions in an experiment carried out in space during the first Spacelab Life Science Mission. Activation, measure...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260400815
更新日期:1992-10-20 00:00:00
abstract::Maintenance of high cell viability was the main characteristic of our new strains of thermotolerant Saccharomyces. Total sugar conversion to ethanol was observed for sugarcane juice fermentation at 38-40 degrees C in less than 10 h and without continuous aeration of the culture. Invertase activity differed among the s...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260370606
更新日期:1991-03-15 00:00:00
abstract::The investigation of new adjuvants is essential for the development of efficacious vaccines. Chitosan (CS), a derivative of chitin, has been shown to act as an adjuvant, improving vaccine-induced immune responses. However, the effect of CS molecular weight (MW) on this adjuvanticity has not been investigated, despite ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27647
更新日期:2020-12-07 00:00:00
abstract::Although sophorolipids (SLs) produced by S. bombicola are a real showcase for the industrialization of microbial biosurfactants, some important drawbacks are associated with this efficient biological process, e.g., the simultaneous production of acidic and lactonic SLs. Depending on the application, there is a require...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25815
更新日期:2016-03-01 00:00:00
abstract::A refolding strategy was described for on-column refolding of recombinant human interferon-gamma (rhIFN-gamma) inclusion bodies by expanded bed adsorption (EBA) chromatography. After the denatured rhIFN-gamma protein bound onto the cation exchanger of STREAMLINE SP, the refolding process was performed in expanded bed ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20763
更新日期:2006-03-05 00:00:00
abstract::A model for cometabolism is verified experimentally for a defined methanotrophic mixed culture. The model includes the effects of cell growth, endogenous cell decay, product toxicity, and competitive inhibition with the assumption that cometabolic transformation rates are enhanced by reducing power obtained from oxida...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19971205)56:5<492::AID-BIT
更新日期:1997-12-05 00:00:00
abstract::Rare sugars have various known biological functions and potential for applications in pharmaceutical, cosmetics, and food industries. Here we designed and constructed a recombination pathway in Corynebacterium glutamicum, in which dihydroxyacetone phosphate (DHAP), an intermediate of the glycolytic pathway, and a vari...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25345
更新日期:2015-01-01 00:00:00
abstract::Gene transcription is regulated by transcription factors that can bind to specific regions on DNA. Antigene oligonucleotides (oligos) can bind to specific regions on DNA and form a triplex with the double-stranded DNA. The triplex can competitively inhibit the binding of transcription factors and, as a result, transcr...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20001120)70:4<467::aid-bit13>3.0
更新日期:2000-11-20 00:00:00
abstract::Highly substituted polychlorinated biphenyls (PCBs) are known to be very resistant to aerobic biodegradation, particularly the initial attack by biphenyl dioxygenase. Functional evolution of the substrate specificity of biphenyl dioxygenase was demonstrated by DNA shuffling and staggered extension process (StEP) of th...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19990605)63:5<544::aid-bit
更新日期:1999-06-05 00:00:00
abstract::Two general models for batch simultaneous enzymatic and microbial reaction (SEMR) processes are presented, the second derived from and simpler than the first and accounting for enzyme denaturation. Using the second model and parameter values from the literature, simulation was used to examine a range of enzyme additio...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260371114
更新日期:1991-05-01 00:00:00
abstract::A key challenge for bioprocess engineering is the identification of the optimum process conditions for the production of biochemical and biopharmaceutical compounds using prokaryotic as well as eukaryotic cell factories. Shake flasks and bench-scale bioreactor systems are still the golden standard in the early stage o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27338
更新日期:2020-07-01 00:00:00