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 transfection with a GFP expression vector, the proportion of GFP-positive cells as determined by flow cytometry was fourfold higher for the PEI transfection as compared to the CaPO4 transfection. However, the mean level of transient GFP expression for the cells with the highest level of fluorescence was twofold greater for the CaPO4 transfection. Fluorescence in situ hybridization on metaphase chromosomes from pools of cells grown under selective pressure demonstrated that plasmid integration always occurred at a single site regardless of the transfection method. Importantly, the copy number of integrated plasmids was measurably higher in cells transfected with CaPO4. The efficiency of recombinant cell line recovery under selective pressure was fivefold higher following PEI transfection, but the average specific productivity of a recombinant antibody was about twofold higher for the CaPO4-derived cell lines. Nevertheless, no difference between the two transfection methods was observed in terms of the stability of protein production. These results demonstrated the feasibility of generating recombinant CHO-derived cell lines by PEI transfection. However, this method appeared inferior to CaPO4 transfection with regard to the specific productivity of the recovered cell lines.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Chenuet S,Martinet D,Besuchet-Schmutz N,Wicht M,Jaccard N,Bon AC,Derouazi M,Hacker DL,Beckmann JS,Wurm FMdoi
10.1002/bit.21972subject
Has Abstractpub_date
2008-12-01 00:00:00pages
937-45issue
5eissn
0006-3592issn
1097-0290journal_volume
101pub_type
杂志文章abstract::The sec-alcohol dehydrogenase activity of whole cells of Rhodococcus ruber DSM 44541 has been employed as an efficient biocatalytic redox system due to the use of acetone and 2-propanol at elevated concentrations for cofactor regeneration in the oxidation and reduction mode, respectively, and external addition of NADH...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10540
更新日期:2003-03-30 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::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
abstract::Bioluminescence from the lux-based bacterial reporter Pseudomonas fluorescens HK44 was experimentally investigated under growth substrate-rich and limiting conditions in batch, continuous stirred tank (CSTR), and turbidostat reactors. A mechanistically based, mathematical model was developed to describe bioluminescenc...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10475
更新日期:2003-02-05 00:00:00
abstract::An innovative type of biofilm model is derived by combining an individual description of microbial particles with a continuum representation of the biofilm matrix. This hybrid model retains the advantages of each approach, while providing a more realistic description of the temporal development of biofilm structure in...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20917
更新日期:2006-08-05 00:00:00
abstract::Hydrogen production by Rhodobacter capsulatus is an anaerobic, photobiological process requiring specific mixing conditions. In this study, an innovative design of a photobioreactor is proposed. The design is based on a plate-type photobioreactor with an interconnected meandering channel to allow culture mixing and H2...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27656
更新日期:2020-12-15 00:00:00
abstract::CHO cells express glycoproteins containing both the N-acetylneuraminic acid (Neu5Ac) and minor amounts of the N-glycolylneuraminic acid (Neu5Gc) forms of sialic acid. As Neu5Gc is not expressed in humans and can be recognized as a foreign epitope, there is the potential for immunogenicity issues for glycoprotein thera...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22644
更新日期:2010-04-15 00:00:00
abstract::A model that was used to describe toxicity from high concentrations of chlorinated aliphatic hydrocarbons (CAHs) on reductively dechlorinating cultures in batch reactors (Sabalowsky and Semprini (in press)) was extended here to simulate observations in continuous flow suspended and attached growth reactors. The reduct...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22822
更新日期:2010-10-15 00:00:00
abstract::This research focused on how the extent and type of primary solid-liquid separation can affect the performance of guard filtration and chromatography, in this instance hydrophobic interaction chromatography. The system used in the study was yeast (Saccharomyces cerevisiae) with the target molecule being an intracellul...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21823
更新日期:2008-08-01 00:00:00
abstract::Static and dynamic characteristics of continuous cultures of recombinant methylotrophs, which are designed to improve the selectivity of plasmid-bearing cells and the plasmid stability, are investigated in detail. Operational regions in which coexistence (survival of plasmid-bearing and plasmid-free cells) operation i...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260290802
更新日期:1987-06-01 00:00:00
abstract::One of the major bottlenecks in the bioconversion of lignocelluosic feedstocks to liquid ethanol is the recalcitrance of residue following pretreatment, specifically softwood derived residues. Peroxide delignification has previously been shown to effectively aid in the removal of condensed lignaceous moieties from sub...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22768
更新日期:2010-08-15 00:00:00
abstract::Temperature shifting was investigated as a means of improving cloned-gene product yields form a recombinant Escherichia coli containing the temperature-sensitive plasmid, pOU 140. In a series of shaker flask fermentations recombinant cells were thermally induced for different time periods. The growth, stability, and p...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260290416
更新日期:1987-03-01 00:00:00
abstract::The solution structure of plasmid DNA is known to be a strong function of solution conditions due to intramolecular electrostatic interactions between the charged phosphate groups along the DNA backbone. The objective of this work was to determine whether it was possible to enhance the use of ultrafiltration for separ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25836
更新日期:2016-04-01 00:00:00
abstract::Cancer is the leading cause of death in industrialized countries. Cancer therapy often involves monoclonal antibodies or small-molecule drugs, but carbohydrate-binding lectins such as mistletoe (Viscum album) viscumin offer a potential alternative treatment strategy. Viscumin is toxic in mammalian cells, ruling them o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27076
更新日期:2019-09-01 00:00:00
abstract::Utilization of renewable feedstocks for the production of bio-based chemicals such as d-lactic acid by engineering metabolic pathways in the yeast Saccharomyces cerevisiae has recently become an attractive option. In this study, to realize efficient d-lactic acid production by S. cerevisiae, the expression of 12 glyco...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26330
更新日期:2017-09-01 00:00:00
abstract::Point and 95% confidence interval estimates of the true growth yield and maintenance coefficient are reported for four pure cultures andtwo mixed cultures of Lactobacillus bulgaricus and Streptococcus thermophilus grown anaerobically on 3% nonfat dry milk using batch followed by fed batch culture. An improved method o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280619
更新日期:1986-06-01 00:00:00
abstract::The laminate consisted of several polymer layers, aluminium, and one cellulose-based layer containing the active enzymatic system (e.g., glucose oxidase, catalase, glucose, and CaCO3). During the industrial lamination process, the enzyme layer was exposed to three temperature spikes up to 325 degrees C without signifi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10266
更新日期:2002-07-05 00:00:00
abstract::The kinetics of cellular reproduction and the rate and extent of synthesis of extracellular polymeric substances (EPS) were investigated for P. aeruginosa growing in glucose-limited chemostats. mu(max) and K(s) estimates of 0.4 h(-1) and 2 mg glucose C/L, respectively, at 25 degrees C were obtained for this bacterium....
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260261203
更新日期:1984-12-01 00:00:00
abstract::Glucose oxidase, invertase, and amyloglucosidase were entrapped in calcium alginate gels as concanavalin A complexes in order to prevent the leaching out of the enzymes from the porous matrix. The free as well as the gel-entrapped concanavalin A-glycoenzyme complexes exhibited a relatively high effectiveness factor, e...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260270803
更新日期:1985-08-01 00:00:00
abstract::An acetate-rich wastewater, containing 170 mg/L of total organic carbon (TOC), 13 mg/L of N, and 15 mg/L of P, was treated using the enhanced biological phosphate removal (EBPR) process operated in a sequencing batch reactor. A slight change of pH of the mixed liquor from 7.0 to 6.5 led to a complete loss of phosphate...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20589
更新日期:2005-10-20 00:00:00
abstract::A thermodynamic model was used in this study to predict the adhesion of Phanerochaete chrysosporium INA-12 as conidiospores or mycelium to various solid carriers. Theoretical predictions were closely reflected by experimental results. Amount of immobilized mycelium was higher for hydrophobic (polypropylene and polyure...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260350505
更新日期:1990-03-05 00:00:00
abstract::The mouse mammary tumor virus (MMTV) promoter is induced by the addition of a glucocorticoid hormone or analog such as dexamethasone. The hormone binds to its specific transcription factor, glucocorticoid receptor (GR), and the activated complex then binds to the glucocorticoid response elements (GREs) in the enhancer...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:2000-01-20 00:00:00
abstract::We performed a macrokinetic and quantitative microbial investigation of a continuously operating bench-scale biofilter treating styrene-polluted gases. The device was filled with a mixture of peat and glass beads as packing medium and inoculated with the styrene-oxidizing strain, Rhodococcus rhodochrous AL NCIMB 13259...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10640
更新日期:2003-07-05 00:00:00
abstract::Traditional biological treatment models are "deduced" from formal chemical kinetics or dynamics of pure microorganism cultures growth. The best formal models give reasonable approximations of the biological treatment model with an ecosystem adaptation (ESA model). The model presented here explains some features of the...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260250610
更新日期:1983-06-01 00:00:00
abstract::Embryonic stem cells (ESCs) are an important source of cardiomyocytes for regenerating injured myocardium. The successful use of ESC-derived cardiomyocytes in cardiac tissue engineering requires an understanding of the important scaffold properties and culture conditions to promote cell attachment, differentiation, or...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.23353
更新日期:2012-03-01 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::An automated system with semi on-line monitoring of glucose, lactic acid, protein, and optical density during lactic acid fermentations, is set up to study the dynamics of lactic acid bacteria. The analyzers for glucose, lactic acid, and protein are based on flow injection analysis (FIA). The system consists of a labo...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260330908
更新日期:1989-04-05 00:00:00
abstract::The selectivity of protein extraction by reversed micellar solutions can be improved by the addition of affinity cosurfactants bearing ligands which bind strongly to the target protein. The interactions between cosurfactant and protein, as well as the interfacial activity of both the free cosurfactant and the protein-...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260421011
更新日期:1993-11-20 00:00:00
abstract::The influence of five different N-terminal protecting groups (For, Ac, Boc, Z, and Fmoc) and reaction conditions (temperature and dimethylformamide content) on the alpha-chymotrypsin-catalyzed synthesis of the dipeptide derivative X-Phe-Leu-NH(2) was studied. Groups such as For, Ac, Boc, and Z always rendered good pep...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260390509
更新日期:1992-03-05 00:00:00
abstract::A desirable feature of many therapeutic glycoprotein production processes is to maximize the final sialic acid content. In this study, the effect of applying a novel chemical analog of the sialic acid precursor N-acetylmannosamine (ManNAc) on the sialic acid content of cellular proteins and a model recombinant glycopr...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26291
更新日期:2017-08-01 00:00:00