Abstract：
:The polysaccharide xanthan which is produced by the γ-proteobacterium Xanthomonas campestris is used as a food thickening agent and rheologic modifier in numerous food, cosmetics and technical applications. Its great commercial importance stimulated biotechnological approaches to optimize the xanthan production. By targeted genetic modification the metabolism of Xanthomonas can be modified in such a way that the xanthan production efficiency and/or the shear-thickening potency is optimized. Using atomic force microscopy (AFM) the secondary structure of single xanthan polymers produced by the wild type Xanthomonas campestris B100 and several genetically modified variations were analyzed. We found a wide variation of characteristic differences between xanthan molecules produced by different strains. The structures ranged from single-stranded coiled polymers to branched xanthan double-strands. These results can help to get a better understanding of the polymerization- and secretion-machinery that are relevant for xanthan synthesis. Furthermore, we demonstrate that the xanthan secondary structure strongly correlates with its viscosifying properties.
journal_name
J Biotechnoljournal_title
Journal of biotechnologyauthors
Teckentrup J,Al-Hammood O,Steffens T,Bednarz H,Walhorn V,Niehaus K,Anselmetti Ddoi
10.1016/j.jbiotec.2016.11.032subject
Has Abstractpub_date
2017-09-10 00:00:00pages
2-8eissn
0168-1656issn
1873-4863pii
S0168-1656(16)31634-0journal_volume
257pub_type
杂志文章abstract：:Different systems are being studied and used to prepare recombinant proteins for pharmaceutical use. The blood, and still more the milk, from transgenic animals appear a very attractive source of pharmaceuticals. The cells from these animals are expected to produce well-matured proteins in potentially huge amounts. Se...
journal_title：Journal of biotechnology
pub_type： 杂志文章,评审
doi：10.1016/0168-1656(94)90062-0
更新日期：1994-05-31 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：:Using an RT-PCR approach a cDNA clone, designated Ms-Rac4 and putatively coding for a small GTPase was isolated from Medicago sativa. Ms-Rac4 and the earlier described Ms-Rac1 [Mol. Gen. Genet. 263 (2000) 761] belong to the class of GTP-binding Rho of plants (Rop) proteins. At the amino acid level they display all con...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2004.04.030
更新日期：2004-08-26 00:00:00
abstract：:The marine microalga Nannochloropsis oculata is a potential source of eicosapentaenoic acid (EPA, C20:5n3) and carotenoids for use in functional foods and nutraceuticals. Mixotrophic culture of N. oculata using glycerol was examined as a possible way of increasing the biomass and metabolite productivity relative to a ...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2016.10.006
更新日期：2016-12-10 00:00:00
abstract：:Stem cell sensors have emerged as a promising technique to electrochemically monitor the functional status and viability of stem cells. However, efficient electrochemical analysis techniques are required for the development of effective electrochemical stem cell sensors. In the current study, we report a newly develop...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2013.04.007
更新日期：2013-06-20 00:00:00
abstract：:A system for streptavidin detection using biotin conjugated to nano-sized bacterial magnetic particles (BMPs) has been developed. BMPs, isolated from magnetic bacteria, were used as magnetic markers for magnetic force microscopy (MFM) imaging. The magnetic signal was obtained from a single particle using MFM without a...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2005.06.028
更新日期：2005-11-21 00:00:00
abstract：:In this article, we review how molecular modeling techniques can be used to shed light on how water and organic solvents influence the reactivity of enzymes. The application of thermodynamics-based models allowed the first qualitative predictions on the selectivity of many reaction types. However, it was with the appl...
journal_title：Journal of biotechnology
pub_type： 杂志文章,评审
doi：10.1016/s0168-1656(02)00034-2
更新日期：2002-06-13 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：:Oxygen tension regulates the biological characteristics of hematopoietic stem and progenitor cells (HSPCs) by modulating intracellular reactive oxygen species (ROS). To better understand oxygen tension mechanism on HSPCs culture, gene expression analysis of human CD34(+)CD38(-) HSPCs was performed using microarrays. T...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2012.01.017
更新日期：2012-04-15 00:00:00
abstract：:A stably transformed insect cell expression system is superior to a baculovirus expression system, since the expression system is sustained and there is no cell lysis, but the isolation of cell lines producing recombinant proteins is time-consuming and laborious. In this study, we developed a technique for the rapid i...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2010.03.011
更新日期：2010-05-17 00:00:00
abstract：:Magnetic Fe3O4 nanoparticles were prepared and embedded into the Combi-CLEAs to produce the magnetic Combi-CLEAs in this work. The process for magnetic Combi-CLEAs preparation was optimized, and its properties were investigated. The optimum temperature, thermal stability and optimum pH of magnetic Combi-CLEAs were sim...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2018.02.007
更新日期：2018-04-10 00:00:00
abstract：:Proteins are multifunctional: their amino acid sequences simultaneously determine folding, function and turnover. Correspondingly, evolution selected for compromises between rigidity (stability) and flexibility (folding/function/degradation), to the result that generally the free energy of stabilization of globular pr...
journal_title：Journal of biotechnology
pub_type： 杂志文章,评审
doi：10.1016/s0168-1656(00)00236-4
更新日期：2000-05-26 00:00:00
abstract：:Sugarcane bagasse (SCB) is an abundant, renewable and inexpensive agricultural byproduct for the production of biofuel and other biobased products. To effectively saccharify SCB with cellulases, combination with dilute alkali salts Na2SO3/Na3PO4 (0.4% Na3PO4, 0.03% Na2SO3) at 7.5% sulfidity and hot water (DASHW) in "o...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2017.08.004
更新日期：2017-10-10 00:00:00
abstract：:Steady state studies in a chemostat enable the control of microbial growth rate at defined reaction conditions. The effects of bacteriophage M13 infection on maximum growth rate of Escherichia coli JM109 were studied in parallel operated chemostats on a milliliter-scale to analyze the steady state kinetics of phage pr...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2017.06.409
更新日期：2017-09-20 00:00:00
abstract：:Two different approaches of matrix assisted refolding have been evaluated and compared to conventional refolding by dilution. Bovine alpha-lactalbumin was used for the studies as model protein. It was adsorbed under denaturing conditions on an ion exchange matrix and refolding was completed on the column prior to elut...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2005.01.004
更新日期：2005-04-20 00:00:00
abstract：:Understanding the causes of discrepancies in pH readings of a sample can allow more robust pH control strategies to be implemented. It was found that 59.4% of differences between two offline pH measurement technologies for an historical dataset lay outside an expected instrument error range of ±0.02pH. A new variable,...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2017.04.025
更新日期：2017-06-10 00:00:00
abstract：:A system has been developed for the release of heterologous proteins from Saccharomyces cerevisiae, based on the use of thermosensitive osmotic-remedial mutants, deficient in cell integrity, that lyse at the non-permissive temperature, thus releasing the bulk of intracellular proteins and leaving behind cell ghosts an...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/0168-1656(94)90149-x
更新日期：1994-11-30 00:00:00
abstract：:Gene silencing experiments in difficult-to-transfect cells are often hampered by the presence of a background of untransfected cells. We present proof-of-concept data from two different strategies for enrichment of siRNA-transfected cells. In the first approach, a heterologous surface antigen is expressed from a plasm...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2007.04.018
更新日期：2007-06-30 00:00:00
abstract：:The present study aims to valorize chestnut burrs, an important lignocellulosic waste, through a biorefinery concept. A solid residue rich in glucan (41.36 ± 0.59 %) and lignin (39.06 ± 0.01 %) obtained from a previous process of pre-hydrolysis was subjected to four treatments with water or NaOH to enhance enzymatic h...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2021.01.010
更新日期：2021-01-18 00:00:00
abstract：:There are currently four crystal structures of low molecular weight endo-1,4-beta-xylanases (E.C.3.2.1.8), i.e. family G/11 xylanases, available at the Brookhaven Data Bank: 2 xylanases from Trichoderma reesei (Törrönen et al., 1994; Törrönen and Rouvinen, 1995) and one from Bacillus circulans and another from Trichod...
journal_title：Journal of biotechnology
pub_type： 杂志文章,评审
doi：10.1016/s0168-1656(97)00095-3
更新日期：1997-09-16 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：:To overcome the low efficiency of agronomic protection from maize dwarf mosaic disease, susceptible maize inbred line was transformed by Agrobacterium tumefaciens harboring hpRNA expression vectors containing inverted-repeat sequences of different lengths targeting coat protein gene (CP) of maize dwarf mosaic virus (M...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2011.03.019
更新日期：2011-05-20 00:00:00
abstract：:Streptavidin is tetrameric protein which has tight and specific biotin binding affinity, and streptavidin modification of proteins or small molecules is widely used for biotechnology tool. Here, we demonstrate site-specific streptavidin-protein conjugation using enzymes. We focused on sortase A, a transpeptidase from ...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2011.01.008
更新日期：2011-03-10 00:00:00
abstract：:Two extra-cellular endoxylanases (Xyl Ia and Ib) were purified to homogeneity from the newly isolated thermophilic fungus, Myceliophthora sp. IMI 387099. Xyl Ia and Ib, having a molecular mass of approximately 53 kDa and pI of 5.2 and 4.8, respectively, were optimally active at 75 degrees C and at pH 6.0. They were st...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2003.12.010
更新日期：2004-04-29 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：:To study the influence of N-linked carbohydrate moiety on the catalytic and biochemical properties of glycosylated enzyme, a recombinant β-d-glucuronidase (PGUS-P) from Penicillium purpurogenum as a model glycoprotein, was deglycosylated with peptide-N-glycosidase F (PNGase-F) under native conditions. The enzymatic de...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2011.12.017
更新日期：2012-02-10 00:00:00
abstract：:We report the design and characterization of novel fusion proteins, consisting of the F8 antibody and of murine calreticulin (Calr). The F8 antibody recognizes the alternatively-spliced ED-A domain of fibronectin, an extracellular matrix component found in most tumor types, while calreticulin has previously been descr...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2018.12.007
更新日期：2019-01-20 00:00:00
abstract：:Superoxide dismutases are ubiquitous enzymes which play an important role in protecting cells against oxidative damage and which have also been shown to contribute to the pathogenicity of many bacterial species. Here we demonstrate that Vibrio cholerae, the causative agent of cholerae, expresses an active periplasmic ...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2004.01.002
更新日期：2004-04-08 00:00:00
abstract：:Cannabis sativa L. plants produce a diverse array of secondary metabolites. Cannabis cell cultures were treated with biotic and abiotic elicitors to evaluate their effect on secondary metabolism. Metabolic profiles analysed by (1)H NMR spectroscopy and principal component analysis (PCA) showed variations in some of th...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/j.jbiotec.2009.05.006
更新日期：2009-08-20 00:00:00
abstract：:A new algorithm was developed for the estimation of the metabolic flux distribution based on GC-MS data of proteinogenic amino acids. By using a sensitive GC-MS protocol as well as by combining the global search algorithm such as the genetic algorithm with the local search algorithm such as the Levenberg-Marquardt alg...
journal_title：Journal of biotechnology
pub_type： 杂志文章
doi：10.1016/s0168-1656(02)00316-4
更新日期：2003-03-06 00:00:00
