Abstract:
:A cellulase from Trichoderma reesei was immobilized on Eudragit L-100, a reversibly soluble polymer depending on the pH of the medium. The solubility of the modified cellulase was studied at different pH values. By changing the pH, the adsorption equilibrium of the derivatized proteins is switched towards the liquid phase, thus making recycling possible. This method allows for improved stability, without major loss of specific activity. The adsorption of cellulase on Eudragit lowers the enthalpy of denaturation, but affects only slightly the denaturation temperature. The use of carbodiimide was ineffective on linking the enzymes covalently to the polymer, since the immobilization process was found to be only mediated by non-covalent forces.
journal_name
J Biotechnoljournal_title
Journal of biotechnologyauthors
Dourado F,Bastos M,Mota M,Gama FMdoi
10.1016/s0168-1656(02)00178-5subject
Has Abstractpub_date
2002-10-23 00:00:00pages
121-31issue
2eissn
0168-1656issn
1873-4863pii
S0168165602001785journal_volume
99pub_type
杂志文章abstract::Poly(methyl methacrylate-acrylic acid) microspheres were prepared and the acid groups were activated by using either carbodiimide (CDI) or thionyl chloride (SOCl2). alpha-Amylase was covalently bound on these activated microspheres. The properties of the immobilized enzyme were investigated and compared with those of ...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/s0168-1656(97)00179-x
更新日期:1998-02-05 00:00:00
abstract::The development and optimization of a purification process of monoclonal antibodies based on two continuous chromatography steps for capture and intermediate purification are presented. The two chromatography steps were individually optimized using either batch chromatography or sequential multicolumn chromatography (...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2015.04.026
更新日期:2015-11-10 00:00:00
abstract::Aspergillus niger AB1.13 cultures with glucoamylase production (with D-glucose as substrate) and without glucoamylase production (with D-xylose as substrate) were characterized by metabolic flux analysis. Two comprehensive metabolic models for d-glucose- as well as for D-xylose-consumption were used to quantify and co...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2007.08.034
更新日期:2007-12-01 00:00:00
abstract::Development of reagentless biosensors implies the tight and functional immobilisation of biological recognition elements on transducer surfaces. Specifically, in the case of amperometric enzyme electrodes, electron-transfer pathways between the immobilised redox protein and the electrode surface have to be established...
journal_title:Journal of biotechnology
pub_type: 杂志文章,评审
doi:10.1016/s1389-0352(01)00058-7
更新日期:2002-02-01 00:00:00
abstract::A sensitive and highly selective method for the simultaneous determination of purine bases and their nucleosides is proposed. An amperometric flow-injection system with the two immobilized enzyme reactors (guanase immobilized reactor and purine nucleoside phosphorylase/xanthine oxidase co-immobilized reactor) is used ...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/0168-1656(90)90021-3
更新日期:1990-04-01 00:00:00
abstract::Old yellow enzymes (OYEs, EC 1.6.99.1) are flavin-dependent oxidoreductases that catalyze the stereoselective trans-hydrogenation of the double bond, representing a promising alternative to metal-based catalysis. Bioconversion of ketoisophorone (KIP) by 28 non-conventional yeasts belonging to 16 different species was ...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2011.08.033
更新日期:2011-12-20 00:00:00
abstract::Flow cytometry was used to demonstrate the presence of beta-lactoglobulin (betaLG) receptors on living murine hybridoma MARK-3 cells using a fluorescein isothiocyanate-betaLG conjugate (FITC-betaLG: molar ratio of 5:1). A site occupation curve was produced using a shift in the mean channel fluorescence at various conc...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/s0168-1656(00)00210-8
更新日期:2000-03-10 00:00:00
abstract::The production of isoprenoids in recombinant microbes for flavor & fragrance, pharmaceutical, agricultural or fuel applications is a booming research field. Isoprenoid extraction from natural resources and chemical synthesis is frequently neither ecological nor commercially profitable. However, recombinant microbes al...
journal_title:Journal of biotechnology
pub_type: 杂志文章,评审
doi:10.1016/j.jbiotec.2016.03.051
更新日期:2016-10-10 00:00:00
abstract::In this work it is describe for the first time, the use of an esterase with null activity (Tfu_0883 bacterial cutinase from Thermobifida fusca) on the removal of fat from the surface of a cotton substrate. Similar levels of fat removal were found for both null and wild-type proteins, despite that only wild type protei...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2012.06.019
更新日期:2012-10-31 00:00:00
abstract::Recombinant Escherichia coli clones encoding between 0 and 6 copies of the mammalian cytochrome b5 gene were subjected to pyrolysis mass spectrometry (PyMS). To deconvolute the pyrolysis mass spectra so as to obtain quantitative information on the amount of cytochrome b5 produced fully-interconnected feedforward artif...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/0168-1656(94)90088-4
更新日期:1994-05-15 00:00:00
abstract::There are many examples of enzymes that share substrates or cofactors in a cyclic manner. Techniques have been developed that use cyclic enzyme systems to assay quantitatively small amounts of biochemical substances (cofactor, substrate), however, only a few studies of the control of these systems have been published....
journal_title:Journal of biotechnology
pub_type: 杂志文章,评审
doi:10.1016/0168-1656(92)90064-g
更新日期:1992-06-01 00:00:00
abstract::Oxygen is a key substrate in animal cell metabolism. It has been reported that the oxygen uptake rate (OUR) is a good indicator of cellular activity, and even under some conditions, a good indicator of the number of viable cells. The measurement of OUR is difficult due to many different reasons. In particular, the ver...
journal_title:Journal of biotechnology
pub_type: 杂志文章,评审
doi:10.1016/s0168-1656(98)00046-7
更新日期:1998-08-12 00:00:00
abstract::Medium composition and cultivation conditions were constructed for the optimum production of leupeptin by Streptomyces exfoliatus SMF13. The production of leupeptin was related to mycelial growth, being optimum in the cultivation with glucose-excess, phosphate-limited, and casamino acids medium. However, leupeptin-ina...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/0168-1656(95)00061-t
更新日期:1995-08-15 00:00:00
abstract::Hepatocyte growth factor (HGF) is biosynthesized as a biologically inactive, single-chain form (pro-HGF). Its activation is associated with cleavage at Arg494-Val495 into a two-chain mature form composed of disulfide-linked alpha- and beta-chains. Because serum is a major source of HGF activator (the predominant serin...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2007.11.006
更新日期:2008-02-29 00:00:00
abstract::Rufibacter tibetensis strain 1351, isolated from the soil of the Tibet plateau of China, belongs to the family of Cytophagaceae. It is a red-pigmented, gram-negative, strictly aerobic and rod-shaped bacterium and shows resistance to UV radiation. Here, we report its complete genome sequence, which can help us find the...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2015.10.015
更新日期:2015-12-20 00:00:00
abstract::The sesquiterpene (+)-valencene is an aroma compound of citrus fruits and is used to flavor foods and drinks. Biosynthesis of (+)-valencene starts from farnesyl pyrophosphate, an intermediate of carotenoid biosynthesis. Corynebacterium glutamicum, the workhorse of the million-ton scale amino acid industry, is naturall...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2014.05.032
更新日期:2014-12-10 00:00:00
abstract::Herbaspirillum seropedicae is a nitrogen-fixing bacterium found in association with economically important gramineae. Regulation of nitrogen fixation involves the transcriptional activator NifA protein. The regulation of NifA protein and its truncated mutant proteins is described and compared with that of other nitrog...
journal_title:Journal of biotechnology
pub_type: 杂志文章,评审
doi:10.1016/s0168-1656(01)00343-1
更新日期:2001-10-04 00:00:00
abstract::Glutathione (GSH) is an important bioactive tripeptide and widely used in food, medicine and other industries. Recently, the bifunctional glutathione synthetase, GshF, has been applied for efficient GSH production under inducible promoter. In this study, the constitutive expression of GshF from Streptococcus sanguinis...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2018.11.001
更新日期:2019-01-10 00:00:00
abstract::Pimprinine, an extracellular alkaloid has been isolated from the culture filtrate of Streptomyces CDRIL-312. Pimprinine was subsequently purified using silica gel column chromatography and also by preparatory thin layer chromatography. Some physicochemical properties, antimicrobial activities (in-vitro) and pharmacolo...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/s0168-1656(01)00244-9
更新日期:2001-06-01 00:00:00
abstract::Aspergillus oryzae finds wide application in the food, feed, and wine industries, and is an excellent cell factory platform for production of organic acids. In this work, we achieved the overproduction of L-malate by rewiring the reductive tricarboxylic acid (rTCA) pathway and L-malate transport pathway of A. oryzae N...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2017.05.011
更新日期:2017-07-10 00:00:00
abstract::The expression of recombinant yeast pyruvate carboxylase (PYC) in animal cell lines was shown in previous studies to reduce significantly the formation of waste metabolites, although it has translated into mixed results in terms of improved cellular growth and productivity. In this work, we demonstrate that the unique...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2013.11.002
更新日期:2014-01-01 00:00:00
abstract::Unicellular green algae, a promising source for renewable biofuels, produce lipid-rich biomass from light and CO2. Productivity in photo-bioreactors is affected by inhomogeneous light distribution from high cell pigment causing heat dissipation of light energy absorbed in excess and shading of the deep layers. Contras...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2020.12.023
更新日期:2021-01-09 00:00:00
abstract::We previously developed a novel one-step biotransformation process for the production of α-ketoglutarate (α-KG) from L-glutamic acid by a Bacillus subtilis whole-cell biocatalyst expressing an L-amino acid deaminase (pm1) of Proteus mirabilis. However, the biotransformation efficiency of this process was low owing to ...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2014.07.431
更新日期:2014-10-10 00:00:00
abstract::The extraction of 13-hydroperoxide-lyase activity from mint leaves as well as its use for C6-aldehyde production was studied in this work. The enzyme cleaves 13(S)-hydroperoxy-C18 fatty acids into C6-aldehyde and C12-oxo-acid. Two mint species were tested: Mentha veridis and Mentha pulegium. The headspace injection me...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2004.03.005
更新日期:2004-07-01 00:00:00
abstract::A DNA construct containing the human alpha 1-antitrypsin gene including 1.5 and 4 kb of 5' and 3' flanking sequences, was microinjected into the pronucleus of rabbit embryos. The recombinant human protein was (a) expressed in the blood circulation of F0 and F1 transgenic rabbits at an average concentration of 1 mg ml-...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/0168-1656(91)90247-s
更新日期:1991-05-01 00:00:00
abstract::Traditional strategies for production of thermo-induced recombinant protein in Escherichia coli consist of a two-phase culture, with an initial growth stage at low temperature (commonly 30°C) followed by a production stage where temperature is increased stepwise (commonly up to 42°C). A disadvantage of such strategies...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2013.06.001
更新日期:2013-08-10 00:00:00
abstract::Glucose oxidase (GOD) was immobilized on cellulose acetate-polymethylmethacrylate (CA-PMMA) membrane. The immobilized GOD showed better performance as compared to the free enzyme in terms of thermal stability retaining 46% of the original activity at 70 degrees C where the original activity corresponded to that obtain...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2005.08.019
更新日期:2006-02-10 00:00:00
abstract::Xylanase T-6 is a thermostable alkaline-tolerant enzyme that is produced by Bacillus stearothermophilus T-6. Xylanase T-6 was found to bleach pulp effectively at pH 9 and 65 degrees C and was used successfully on an industrial-scale mill trial. To facilitate the future characterization of the protein via X-ray analysi...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/s0168-1656(96)01604-5
更新日期:1996-11-15 00:00:00
abstract::Reteplase is the third generation of thrombolytic medicine and has many advantages over commercial t-PA. However, over-expressing recombinant reteplase in E. coli always accumulates as inclusion bodies due to nine pairs of disulfide bonds formation that is the main obstacle for correct folding. In this paper, in order...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2014.10.028
更新日期:2014-12-20 00:00:00
abstract::Agrobacterium sp. H13-3, formerly known as Rhizobium lupini H13-3, is a soil bacterium that was isolated from the rhizosphere of Lupinus luteus. The isolate has been established as a model system for studying novel features of flagellum structure, motility and chemotaxis within the family Rhizobiaceae. The complete ge...
journal_title:Journal of biotechnology
pub_type: 杂志文章
doi:10.1016/j.jbiotec.2011.01.010
更新日期:2011-08-20 00:00:00