MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Biotechnology and Applied Biochemistry' source. Sat, 20 Mar 2010 16:01:05 +0100 http://www.medworm.com/index.php?rid=3377652&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090256 The expression of recombinant human interleukin-2 (rhIL-2) in bacteria results in the formation of insoluble inclusion-body aggregates. These aggregates were first solubilized under denaturing conditions (solution of buffer phosphate containing 8 M urea and 10 mM mercaptoethanol) and then purified using immobilized metal affinity chromatography (IMAC). IMAC was used to capture rhIL-2. The protein was gradually refolded on the column by a gradient elution (8 M to 0 M urea) in the presence of 10% glycerol. Glycerol was used to abolish the protein aggregation during the refolding step. By this method, rhIL-2 was collected at 97% purity and its activity was measured by the lymphocyte transformation test (LTT). The measured activity was identical to commercial human interleukin-2. (Source: Biot... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3377652 Thu, 18 Mar 2010 00:00:00 +0100 3377652 http://www.medworm.com/index.php?rid=3334617&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090307 In this study, we tested the hypothesis that mechanical cyclic strain promotes TGF-ß1-mediated cardiomyogenic marker expression of BMMSCs in vitro. The mRNA expression of cardiac-specific gene was more upregulated in BMMSCs cultured with TGF-ß1 supplement and subjected to cyclic strain for one week than in BMMSCs cultured statically with TGF-ß1 supplement. Immunocytochemical analyses and flow cytometric analysis showed that the proportions of cardiac troponin I-positive cells and cardiac myosin heavy chain-positive cells and the proportions of cells expressing tropomyosin, respectively, were more increased by TGF-ß1with cyclic strain than by TGF-ß1 alone. These results showed that cyclic strain promotes TGF-ß1-mediated cardiomyogenic marker express... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3334617 Fri, 05 Mar 2010 00:00:00 +0100 3334617 http://www.medworm.com/index.php?rid=3243108&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090314 The effects of different methods for elevating oxygen transfer rate (OTR) on the foreign gene expression and the cell growth of recombinant Escherichia coli BL21 were investigated. Two strategies were introduced to control dissolved oxygen (DO) levels in the fermentation broth: (i) increasing fermentor pressure; and (ii) supplying oxygen-enriched air. These two methods were compared to the glucose feedback model, which acted as the control. By adopting a fed-batch method of cultivation, the cell yield coefficient (YX/S), accumulation of acetic acid and volumetric product yield (YP) were measured or estimated. Adoption of these two methods led to an improvement in the oxygen transfer rate. The cell density and volumetric product yield in the cultivation controlled by increasing the fermento... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3243108 Fri, 05 Feb 2010 00:00:00 +0100 3243108 http://www.medworm.com/index.php?rid=3235198&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090239 During production of air-filled albumin microspheres to be used as an ultrasound contrast agent, it was observed that some albumin lots could not be used due to albumin precipitation. In order to understand the reason for these lot-to-lot variations 24 lots of 5% (w/v) human albumin pharmaceutical preparations were analyzed. The results revealed that the good albumin lots all contained less than 0.03 mol free SH groups per mol albumin. The precipitation observed with other lots was most probably due to the higher amount of free SH groups. The lower amount of free SH groups in the good lots correlated with: (1) a yellow colour of the solutions and a UV-VIS spectrum similar to that observed for nonenzymatic glycosylation; (2) a decreased fructosamine content; (3) an increased mobility agains... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3235198 Wed, 03 Feb 2010 00:00:00 +0100 3235198 http://www.medworm.com/index.php?rid=3227165&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090248 The inductive effect of L-ascorbate on the microbiological production of 3,4-dihydroxy-L-phenylalanine (L-dopa) from Aspergillus oryzae NRRL-1560 was investigated. All the biochemical reactions were performed aerobically using mould mycelia as a source of enzyme tyrosinase and acetate buffer (pH 3.0) as an extractant. L-tyrosine as substrate was added at a level of 2.5 mg/ml. The maximal L-dopa production (1.876 mg/ml) was achieved when L-ascorbate (5.0 mg/ml) was added 6 min after the initiation of biochemical reaction at 50ºC, consuming 2.144 mg/ml L-tyrosine. The performance of fuzzy logic control of the reaction was found to be highly promising for the improved substrate conversion rate (~80%). After optimizing reaction conditions particularly the addition of L-ascorbate, a tota... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3227165 Mon, 01 Feb 2010 00:00:00 +0100 3227165 http://www.medworm.com/index.php?rid=3227164&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090274 The introduction of different methodologies for construction and screening of complex protein libraries has provided powerful means in protein engineering for development of molecules with desired traits. A challenge faced in many situations is to adapt a given methodology for efficient and rapid identification of the most interesting variants present in a library. In the present study, the concept of Darwinian selection based on a growth advantage for clones having the desired trait has been investigated. Using a β-lactamase-based Protein Fragment Complementation Assay (PCA), an affinity maturation of a TNF-α binding affibody molecule of an initial 2 nM affinity for the target has been performed. Initial characterization of the PCA system, based on the affinity driven recons... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3227164 Mon, 01 Feb 2010 00:00:00 +0100 3227164 http://www.medworm.com/index.php?rid=3193073&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090226 Affibody molecules binding to the site of hormone interaction in the insulin-like growth factor-1 receptor (IGF-1R) were successfully selected by phage display technology employing a competitive elution strategy during biopanning, where release of receptor-bound phagemids was accomplished by competition with insulin-like growth factor-1 (IGF-1). In non-competition selections, elution of receptor-bound phagemids was performed by Imidazole or low pH incubation, which also resulted in isolation of affibody molecules that could bind to the receptor. An ELISA-based assay showed that the affibody molecules generated by IGF-1 competition during elution as well as affibody molecules generated in the non-competitive selections, could compete with IGF-1 for binding to the receptor. The affinities of... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3193073 Wed, 20 Jan 2010 00:00:00 +0100 3193073 http://www.medworm.com/index.php?rid=3148550&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090186 This study investigated the chemical properties and anti-tyrosinase activities of silk sericin (SS) extracted from different Thai silk strains via various extraction methods. Different silk strains contain distinct SS with varying amino acid compositions, which are significantly influenced by the extraction method used. Urea extraction of SS was the only method that provided clearly distinguishable bands and had the most significant impact on SS conformation as illustrated by FT-IR spectra. The use of urea or either acidic or alkaline chemicals in the extraction process also influenced SS thermal behavior. With regard to biological activity, SS extracted using urea exhibited the highest anti-tyrosinase activity, while alkali-degraded SS showed no inhibition of mushroom tyrosinase. Pigments... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3148550 Thu, 07 Jan 2010 00:00:00 +0100 3148550 http://www.medworm.com/index.php?rid=3148549&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090258 Vascular intervention procedures can lead to endothelial damage and expose the underlying vascular smooth muscle cells (VSMC) to shear stress. Although shear stress has been implicated in the proliferation and migration of VSMC, the molecular mechanism(s) underlying these events are not well understood. Here we examine the effect of shear stress on VSMC reorientation and the activation of Akt pathway signaling. Cells were subjected to a shear of 9.8 dynes/cm2 for 0-min, 5-min, 15-min, 30-min, 1h, 4h and 24h. Shear stress caused the VSMC to realign at an angle that was ~450 relative to the shear force vector after 24 hr. Immunoblotting demonstrated that the phosphorylation of Akt and Akt-related signaling proteins (mTOR, PTEN, and p70S6k) were increased following shear stimulation. These da... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3148549 Thu, 07 Jan 2010 00:00:00 +0100 3148549 http://www.medworm.com/index.php?rid=3055934&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090277 A low-cost microbioreactor made polytetrafluoroethylene (PTFE) was used to cultivate a model organism Pseudomonas aeruginosa DS10-129. The progress of bioprocessing was monitored by comparing the growth of the organism in the microbioreactor, conventional bench scale bioreactor and shake flask methods. Under the microbioreactor conditions the organism produced 23mg/ml of pyocyanin that had antimicrobial effect against Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas teessidea and Pseudomonas clemancea. Furthermore, a total of 106μg/ml of effective biosurfactants consisting of dirhamnolipids (RL2) and monorhamnolipids (RL1). The biosurfactants reduced the surface tension of distilled water from 72 mN/m to 27.9mN/m and emulsified kerosene by 71.30%. Th... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3055934 Fri, 04 Dec 2009 00:00:00 +0100 3055934 http://www.medworm.com/index.php?rid=3055933&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090210 Gene delivery into mesenchymal stem cells (MSCs) holds great promise for gene therapy, and lentiviral transduction has recently been shown to be a highly efficient method for gene delivery. Our previous studies indicated that the umbilical cord was a new source of MSCs, however, it was unclear whether the umbilical cord MSCs (UC-MSCs) would retain their characteristics after lentivirus-mediated gene transduction. The aim of this study was to investigate the feasibility of transducing UC-MSCs with lentiviral vectors and to determine whether these transduced stem cells would retain their ability to differentiate into different lineages. Herein, we demonstrated that the percentage of EGFP-positive cells increased with the multiplicity of infection and number of transduction cycles. In additio... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3055933 Fri, 04 Dec 2009 00:00:00 +0100 3055933 http://www.medworm.com/index.php?rid=3014959&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090198 This report describes the antimicrobial activity of chitosan capped gold nanoparticles coupled with ampicillin (C-AuNp-Amp). C-AuNp-Amp was synthesized using wet precipitation method and characterized using Fourier transform infrared spectroscopy (FT-IR) and atomic force microscopy (AFM) techniques. The optimal level of ampicillin concentration that couples with C-AuNp nanocomposite was determined by using UV-Vis spectroscopy. The agar well diffusion method was used to evaluate the antimicrobial activity and the broth dilution assay was used to determine the minimum inhibitory concentration (MIC). The size of the ellipsoidal C-AuNp-Amp particles was found to be in the range of 50 –100 nm. FTIR spectrum confirms the bonding between amino groups of chitosan and carboxylic groups of am... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=3014959 Fri, 20 Nov 2009 00:00:00 +0100 3014959 http://www.medworm.com/index.php?rid=2988330&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090111 This study represented an important step to investigate the characterization for the new pro-apoptosis protein hPNAS-4, which aids to discover new drug targets for development of effective therapeutic approaches to cancer in future. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2988330 Fri, 13 Nov 2009 00:00:00 +0100 2988330 http://www.medworm.com/index.php?rid=2980551&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090215 The present study was conducted to assess the efficiency of a novel cell harvesting method involving dissolution of the culture substrate composed of ferric ion-cross linked alginate (Fe-alginate). Cell harvesting is an essential step for recovery of cultured adherent cells, but conventional methods such as trypsinization or scraping cause considerable damage to the cells. We therefore devised an original method for harvesting cultured cells using Fe-alginate films as a culture substrate, and then retrieving the cells by disintegration of the alginate gel. Fe-alginate was easily dissolved under physiological conditions by exchange of cross-linked ions using chelating agents such as citrate. The effects of this cell harvesting method were investigated in comparison with trypsinization and s... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2980551 Wed, 11 Nov 2009 00:00:00 +0100 2980551 http://www.medworm.com/index.php?rid=2962566&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090218 The effect of several cultivation conditions on the kinetics of bacterial growth and polysaccharide production of S. pneumoniae serotype 14 was studied. The presence in the supernatant of serotype specific capsular polysaccharide (CPS) during growth was followed by size exclusion HPLC and in parallel confirmed by a specific latex reagent. Agitation level did not affect the production behaviour, whereas pH maintenance above 6 strongly enhanced both growth and CPS production throughout the cultivation period in flasks. Production of high molecular weight polysaccharide was found to be largest between 5 to 6 hr cultivation, at the end of the log phase. By laser light scattering, 90 % of this purified CPS product showed a molecular weight range from 350 kDa to 1500 kDa, with an average Mw of 9... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2962566 Thu, 05 Nov 2009 00:00:00 +0100 2962566 http://www.medworm.com/index.php?rid=2938574&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090168 Genes encoding apoptosis-inducing proteins are postulated to be candidate tumor suppressors. The identification of such proteins may benefit the early diagnosis and therapy of tumors. In the current study, we characterized the function of a novel human bone marrow stromal cell (BMSC)-derived protein (IPP5) by large scale random sequencing of a human BMSC cDNA library. Human IPP5 cDNA encodes a protein of 116 amino acid residues, which shares high homology with human inhibitor-1 of protein phosphatase 1 (PPI-1). The effect of IPP5 on apoptosis and the underlying molecular mechanisms were investigated by overexpression of IPP5 in HeLa cells, a human cervical carcinoma cell line. Our results showed that overexpression of active mutant IPP5 inhibited anchorage-dependent growth and induced apop... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2938574 Thu, 29 Oct 2009 00:00:00 +0100 2938574 http://www.medworm.com/index.php?rid=2930383&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090187 In this study, an improved PM isolation technique involving coating intact cells with synthesized cationic silica coated magnetic nanospheres was developed and applied to the proteomic analysis of the PM from human erythroleukemia K562 cells. The Western blotting characterization and the protein identification of the prepared PM indicated that PM enrichment method using the prepared magnetic nanospheres was a fast and inexpensive strategy with high specificity. Our results demonstrate the potential of these cationic silica coated magnetic nanospheres for high-throughput identification of PM proteins from cells. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2930383 Tue, 27 Oct 2009 00:00:00 +0100 2930383 http://www.medworm.com/index.php?rid=2930382&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090214 In conclusion, as a further step in investigating small intestinal tissue engineering the nanocomposite employed in this study may prove to be a useful alternative to PLGA in the future. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2930382 Tue, 27 Oct 2009 00:00:00 +0100 2930382 http://www.medworm.com/index.php?rid=2889848&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090208 A new approach has recently been proposed for the purification of "mammalian-type" immunoglobulin G (IgG), consisting of exclusion-binding. The technique uses a gel ("Melon gel", PIERCE) that binds to all plasma proteins but not to IgGs, thus allowing IgGs to be recovered in the flow-through fraction. Here, the technique was applied to camelid IgGs, which are known to be constituted not only of classic mammalian-type IgGs (IgG1) but also of IgGs containing only heavy chains (HC-IgGs). Both mammalian type and HC-IgGs can be purified in the flow-through fraction of dromedary plasma samples with less than 8.5% contamination, by making minor improvements to the conditions recommended by the manufacturer. The contaminant proteins, as determined by liquid chromatography-mass spectrometry/mass sp... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2889848 Tue, 13 Oct 2009 23:00:00 +0100 2889848 http://www.medworm.com/index.php?rid=2875137&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090179 Abstract A simple high yielding process for production of recombinant human growth hormone (rhGH) in Pichia pastoris system is described. The approach, adopted addition of surfactants during fermentation along with methanol induction. Pichia integrant harboring multiple copy, non-codon optimized hGH, showed poor expression in complex and defined medium. Inclusion of surfactants Tween 20 or Tween 80 during induction, enhanced the expression levels significantly in shake flask studies. Combination of 2 liter basal salt medium (BSM) and Tween 20 in bioreactor culminated in 3x104 folds elevated expression of the protein (~500 mg l-1 ) as estimated by ELISA. SDS-PAGE and Western blot analysis revealed that the Pichia derived rhGH migrated as a single band with a molecular weight of ~22 kDa pro... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2875137 Wed, 07 Oct 2009 23:00:00 +0100 2875137 http://www.medworm.com/index.php?rid=2845793&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090219 The efficient enzyme-catalyzed reaction of morpholines as model structures for bioactive compounds with para-dihydroxylated aromatic systems was carried out using the oxidoreductase laccase and atmospheric oxygen to produce eight novel morpholine-substituted aromatics. The laccase of Myceliophthora thermophila was used for cross-linking morpholines containing primary or secondary amino groups with para-dihydroxylated laccase substrates. We demonstrate that not only primary amino groups but also secondary amino groups are able to couple with para-dihydroxylated aromatic systems in laccase-catalyzed reactions. The resulting model products (yields up to 80%) were isolated, structurally characterized and tested for their antibacterial, antifungal, and cytotoxic activities. Four of the eight pr... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2845793 Tue, 29 Sep 2009 23:00:00 +0100 2845793 http://www.medworm.com/index.php?rid=2792707&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090171 Two tropinone reductases constitute a branching point in the biosynthesis of tropane alkaloids. Here we report for the first time the cloning and characterization of two full-length cDNAs encoding AaTRI (GenBank Accession No. EU424321) and AaTRII (GenBank Accession No. EU424322) from Solanaceous plant Anisodus acutangulus by rapid amplification of cDNA ends (RACE). Sequence comparison results indicated AaTRI and AaTRII had high homology with other tropinone reductases from Hyoscyamus niger, Datura stramonium etc, but AaTRI and AaTRII only showed identity of 60.8%. Phylogenetic tree analysis results showed that AaTRI and AaTRII belonged to different clusters and have the closest relationship with TRI and TRII from H. niger, respectively. Expression pattern analysis founded that AaTRI and Aa... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2792707 Sun, 13 Sep 2009 23:00:00 +0100 2792707 http://www.medworm.com/index.php?rid=2756938&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090222 A novel surface display system was constructed using the cell-wall anchor protein Flo1p from Saccharomydes cerevisiae, the mannanase (man1) from Bacillus subtilis was fused with the C-terminal of Flo1p and the 6×His-tag was inserted between Flo1p and man1. The fusion proteins were confirmed to be displayed on the cell surface of Yarrowia lipolytica successfully by immunofluorescence. Then, the surface-displayed mannanase was characterized. The optimum catalytic conditions for the recombinant mannanase was 55℃at pH 6.0, and it exhibited high stability against pH variation. The highest activity of the recombinant mannanase reached 62.3IU/g (dry cell weight) after the recombinant cultivated for 96 hours in YPD medium. To our knowledge, it was the first report that the high activ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2756938 Mon, 31 Aug 2009 23:00:00 +0100 2756938 http://www.medworm.com/index.php?rid=2704955&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090141 In this study the special shake flasks, so called ventilation flasks find equipped with oxygen sensors and then an unsteady state gas-transfer model for shake flasks was developed and experimentally investigated for a wide range of gas transfer resistances (kplug). For the validation of our unsteady state model to simulate the gas transfer in a biological system in the ventilation flasks, a strain of Corenobacteriu glutamicum DM 1730 was used as a model organism. For further easy processing the resulting total mass-transfer resistance (kplug) is described as a function of the mass flow through the sterile plug (OTRplug) by an empirical equation. This equation is introduced into a simulation model which calculates the gas partial pressures in the head space of the flask. Additionally, the g... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2704955 Sun, 16 Aug 2009 23:00:00 +0100 2704955 http://www.medworm.com/index.php?rid=2673853&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090181 Protein A chromatography has become widely established for the preparative purification of monoclonal antibodies. Low pH elution from Protein A columns followed by neutralization can often lead to precipitation of impurities in the product stream leading to a visually turbid solution. Pre-treatment of the cell culture harvest stream with increased surface area of a depth filter was found to reduce the magnitude of this problem through exploitation of the adsorptive properties of harvest depth filters. However, this was not a complete solution. Clarification of this turbid product stream prior to the polishing chromatographic steps in the downstream process posed significant filtration challenges. Development of a staged filtration process with the use of low plugging glass fiber depth filt... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2673853 Tue, 04 Aug 2009 23:00:00 +0100 2673853 http://www.medworm.com/index.php?rid=2666769&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090125 In this study, the lysozyme retention value (LRV), on the vendor Certificate of Analysis (C of A), was predictive of the performance of a hydrophobic interaction (HIC) resin in a complex manufacturing step. This processing step is used to reduce host cell protein impurities (PI) while maintaining a desired glycoform profile of recombinant Thyroid Stimulating Hormone (TSH). A correlation was found between a first moment analysis of the HIC elution peaks and resin LRV. About 91% of the observed variation was accounted for by resin LRV and LRV of 55 and 50 were significantly different. The acceptable LRV range, to maximize glycoform profile reproducibility and minimize recovery fluctuations, was dependent on the product collection method. Only resins with a narrow LRV range within 1-2 units w... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2666769 Mon, 03 Aug 2009 23:00:00 +0100 2666769 http://www.medworm.com/index.php?rid=2610326&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090116 The hepatitis B virus (HBV) X protein (HBx) is a multifunctional regulator of cellular signal transduction and transcription pathways in host-infected cells. Evidence suggests that HBx has a critical role in the pathogenesis of hepatocellular carcinoma (HCC). However, the lack of efficient large-scale preparation methods for soluble HBx has hindered studies on the structure and function of HBx. Here, a new pMAL-c2x protein fusion and purification system was used for high-level expression of soluble HBx fusion protein. The high-purity fusion protein was obtained via amylose resin and Q-Sepharase chromatography. The untagged HBx was efficiently and rapidly purified by Sephadex G75 chromatography, following cleavage by factor Xa at 23°C. The purity of active HBx protein was >99% wit... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2610326 Wed, 15 Jul 2009 23:00:00 +0100 2610326 http://www.medworm.com/index.php?rid=2555451&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090101 Despite indications that glutaraldehyde (GA) crosslinked tissues remain prone to long-term degradation and calcification, it is still the reagent of choice in the fixation of bioprosthetic heart valves. We have previously shown that increased GA concentrations and diamine extension of crosslinks with lysine incorporation lead to a mitigated in vivo calcification, mainly of porcine aortic wall tissue. The current study was performed to assess the correlation between the crosslink-density of all three commonly used tissue types (porcine aortic wall (PW), porcine aortic leaflet (PL), and bovine pericardium (BP)) after GA±Lysine treatment with tissue calcification in the subcutaneous rat model. The effect of lysine enhancement, and increased GA concentration in the combination with ly... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2555451 Mon, 29 Jun 2009 23:00:00 +0100 2555451 http://www.medworm.com/index.php?rid=2503407&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090085 Affibody molecules specific for human TNFα were selected by phage-display technology from a library based on the 58-residue protein A-derived Z domain. TNFα is a proinflammatory cytokine involved in several inflammatory diseases, and to this day, four TNFα-blocking protein pharmaceuticals have been approved for clinical use. The phage selection generated 18 unique cystein-free affibody sequences of which 12 were chosen, after sequence cluster analysis, for characterization as proteins. Biosensor binding studies of the 12 E. coli-produced and IMAC-purified affibody molecules revealed three variants that demonstrated the strongest binding to human TNFα. These three affibody molecules were subjected to kinetic binding analysis and also tested for their binding to m... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2503407 Mon, 22 Jun 2009 23:00:00 +0100 2503407 http://www.medworm.com/index.php?rid=2503408&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090102 To obtain a better understanding of responsive mechanism of plant cells in response to hydrodynamic mechanical stress, lipid profiling of suspension cultured Taxus chinensis var. mairei cells under shear stress was carried out using LC-MS/MS and GC-TOF-MS. T. chinensis var. mairei cells cultured in Couette type shear reactor responded with an increase of cell membrane permeability compared with control cells, which indicated adaptation to shear stress altered membrane lipid composition. The main changes of lipid profiles in the shear stress induced cells were the following: a) total phospholipids content decreased, especially structural phospholipids such as phosphatidylglycerol, phosphatidylethanolamine, and phosphatidylcholine; b) cells increased stigmasterol at the expense of sitosterol... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2503408 Tue, 16 Jun 2009 23:00:00 +0100 2503408 http://www.medworm.com/index.php?rid=2503409&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090063 In this study, zinc-binding and zinc-free endostar were compared to further characterize the biochemical and structural properties. Thermal-induced denaturation was determined by monitoring changes in the fluorescence emission spectra. The result indicated that zinc binding significantly increased the transition temperature of endostar and contributed to a reversible change in protein conformation after recooling. Proteolysis assays demonstrated that the modified protein binding with zinc ions can stabilize the N-terminus as well as the C-terminus of endostar when treated with trypsin, chymotrypsin, carboxypeptidase A and B. Western blot analyses using anti-His6 antibody confirmed that the major degraded fragments were cleaved in the N-terminus of endostar when treated with trypsin and chy... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2503409 Mon, 15 Jun 2009 23:00:00 +0100 2503409 http://www.medworm.com/index.php?rid=2455848&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090096 The human epidermal growth factor receptor-2 (HER2) and the epidermal growth factor receptor (EGFR) are overexpressed in various forms of cancer, and the co-expression of both HER2 and EGFR has been reported in a number of studies. The simultaneous targeting of HER2 and EGFR has been discussed as a strategy to potentially increase the efficiency and selectivity in molecular imaging and therapy of certain cancers. In an effort to generate a molecule capable of bispecific targeting of HER2 and EGFR, a gene fragment encoding a divalent HER2-binding affibody molecule was genetically fused in frame to a divalent EGFR-binding affibody molecule via a (GGGGS)3-encoding gene fragment. The encoded 30 kDa affibody construct (ZHER2)2-(G4S)3-(ZEGFR)2, with potential for bispecific binding to HER2 and E... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2455848 Wed, 03 Jun 2009 04:00:00 +0100 2455848 http://www.medworm.com/index.php?rid=2413018&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080268 Optimization of refolding conditions for progenipoietin was performed. The molecule has five disulfide bonds and hence, is a challenge to refold. Variables studied included pH, dithiothreitol (DTT) concentration, cystine concentration, urea concentration, protein concentration, dissolution hold time, and oxygen availability. In view of the complexity of the reaction with respect to the number of parameters that can impact the refold efficiency, some variables were examined via single parameter studies while others were looked at via Design of experiments (DOE). The DOE approach allowed us to look at the effect of these variables in wide ranges as well as their interactions in a very efficient manner. We were able to obtain a maximal refolding efficiency of 57%, defined as a % of correctly ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2413018 Wed, 13 May 2009 04:00:00 +0100 2413018 http://www.medworm.com/index.php?rid=2386490&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080250 Inhibition of p53 by pifithrin-α promotes the p53-mediated apoptosis and protects against doxorubicin-induced apoptosis. The present study was carried out to evaluate the effect of pifithrin-α on radioprotective potential of Podophyllum hexandrum fraction (REC-2006) in HepG2 (p53++) cell line. REC-2006 (10-5μg/ml) treatment 2h before irradiation (10Gy) rendered 80±3% protection in HepG2 cells, whereas, pifithrin-α debilitated the radioprotective potential of REC-2006. REC-2006 increased the expression of Hsp70, HSF-1 and Bcl2 in irradiated HepG2 cells, whereas, pifithrin-α when treated with REC-2006 decreased the expression of Hsp70, HSF-1 and Bcl2 in HepG2 cells. REC-2006 facilitated post-irradiation DNA repair by pausing the cell-cy... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2386490 Fri, 01 May 2009 04:00:00 +0100 2386490 http://www.medworm.com/index.php?rid=2323279&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080300 In order to increase the productivity of human interleukin-2, a stoichiometric model has been used to determine the most needed amino acids and a precise value of their amounts to be added to the culture during expression of human interleukin-2 (as a model protein) by recombinant Escherichia coli BL21 [pET21a-hil2]. Experiments have been performed to investigate the effect of chosen amino acids and their interactions on expression of human interleukin-2. Glutamine, the mixture of leucine, aspartic acid, glycine and the mixture of leucine, glutamine, aspartic acid, were the most effective interaction in expression of interleukin-2. Most promising amino acids were then chosen for further experiments at three different levels to find if altering the stoichiometric values can lead to better va... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2323279 Thu, 02 Apr 2009 04:00:00 +0100 2323279 http://www.medworm.com/index.php?rid=2323281&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080273 T-A cloning is the most commonly used molecular cloning technique in which T-vector is the core tool. T-vectors commonly used now are blue-white positive selection vectors based on mechanism of α-complement of β-galactose of E. coli. Disadvantages of these traditional T-vectors in application include insufficient positive rate and the existence of false-positive clones, which, especially the latter, makes screening of transformant clones via colony PCR necessary. In the present study, a novel T-vector, based on the strategy of inhibiting the growth of negative transformants by means of a lethal gene and innovative design of insertion site, was developed. The innovative design of the insertion site for PCR fragments not only guarantees complete blocking of the expression of th... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2323281 Mon, 30 Mar 2009 04:00:00 +0100 2323281 http://www.medworm.com/index.php?rid=2231038&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090012 Epidemiological studies have demonstrated that high-risk human papillomavirus (HPV) is involved in causing cervical carcinoma. The HPV oncoproteins E6 and E7 immortalize human keratinocytes is mostly resulted from inactivation of tumor suppressor proteins p53 and pRB, which also play an important role in regulating the expression of pro- and antiangiogenic factors. The present study was conducted to determine whether IFN--inducible protein 10 (IP-10)/CXC chemokine ligand 10(CXCL10), one of the potent antiangiogenic chemokines, can inhibit the growth of cervical cancer. Plasmid DNA encoding CXCL10 was encapsulated with cationic liposomes, mice were treated with DNA-liposome mixture 6 times with the 5-day interval. Our results demonstrated that CXCL10 could reduce the level of HPV oncoprotei... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2231038 Tue, 03 Mar 2009 05:00:00 +0100 2231038 http://www.medworm.com/index.php?rid=2215112&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20090007 In conclusion, the Leu-d3-based quantitative technique can be effectively expanded to compare the expression levels for tissue proteome at different states, which allows to identify new candidate biomarkers for tumors. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2215112 Thu, 26 Feb 2009 05:00:00 +0100 2215112 http://www.medworm.com/index.php?rid=2198852&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080215 Micron-sized aggregates of a 6050 base pair plasmid obtained by the addition of 1.5-3.0 mM CaCl2 and 20% v/v t-butanol or 0.3-1.0% v/v aluminium phosphate gel were subjected to degradation induced by sonication or vorticular flows. Dynamic light scattering revealed that the plasmid hydrodynamic radius increases from 116 nm to > 1300 nm and ca. 1000 nm, when formulated with CaCl2/t-butanol and aluminium phosphate gel, respectively. Circular dichroism showed that addition of CaCl2/t-butanol leads to a B→ψ (-) transition in the plasmid structure, whereas no detectable transitions were observed for aluminium phosphate gel formulations. The ability of the condensing agents to stabilise supercoiled plasmid isoforms subjected to sonication or turbulent Taylor vortices was assesse... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2198852 Thu, 19 Feb 2009 05:00:00 +0100 2198852 http://www.medworm.com/index.php?rid=2186474&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080266 Nonsense mutations, giving rise to UAA, UGA, UAG stop codons within the coding region of mRNAs, promote premature translational termination and are the leading cause of about 30% of inherited diseases, including cystic fibrosis, Duchenne muscular dystrophy, thalassemia. For instance, in the β039-thalassemia the CAG (Gln) codon is mutated to the UAG stop codon, leading to premature translation termination and to mRNA destabilization through the well described nonsense-mediated mRNA decay (NMD). In order to develop an approach facilitating translation and, therefore, protection from NMD, aminoglycoside antibiotics have been tested on mRNAs carrying premature stop codons. These drugs decrease the accuracy in the codon-anticodon base pairing, inducing a ribosomal read through of premat... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2186474 Fri, 13 Feb 2009 05:00:00 +0100 2186474 http://www.medworm.com/index.php?rid=2169668&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080203 Molecular responses of phospholipids of T. cuspidata cell to hydrodynamic shear stress were investigated by using two bubble columns with different nozzle sizes. T. cuspidata cells cultured in bubble columns responded with an increase of cell membrane permeability when compared with shake flask culture, corresponding to the alteration of phospholipid constitutions. Phospholipid differences between bubble columns and shake flask cultures were analyzed by using LC/ESI-MS coupled with principle component analysis (PCA). It was found that phosphatidic acid (PA) is a main molecular species of potential biomarkers. The PA quantities were found to increase, while phosphatidylcholine (PC) and phosphatidylinositol (PI) quantities decrease after 96 h of cultivation in bubble columns, corresponding t... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2169668 Mon, 09 Feb 2009 05:00:00 +0100 2169668 http://www.medworm.com/index.php?rid=2114954&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080178 A comparative study of regioselective acylation of 5-azacytidine catalyzed by Candida antarctica lipase B (CAL-B) in co-solvent mixtures and in pure organic solvents was made for the first time, and it was showed that a remarkable enhancement in the initial rate and substrate conversion of the reaction could be achieved with co-solvents as the reaction media instead of pure organic solvents. For CAL-B-catalyzed regioselective synthesis of 5'-O-butyryl-5-azacytidine in co-solvent mixtures, the optimal co-solvent mixture, initial water activity, enzyme dosage, the molar ratio of vinyl butyrate to 5-azacytidine and temperature were hexane/pyridine (40/60, v/v), 0.07, 50 U/ml, 15:1 and 60 °C, respectively. Under the optimum conditions, the initial reaction rate, substrate conversion and... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2114954 Mon, 19 Jan 2009 05:00:00 +0100 2114954 http://www.medworm.com/index.php?rid=2025501&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080110 Three different strains of the endophytic fungus, Phomopsis species, were isolated from the healthy leaves of Taxus cuspidata, Ginkgo biloba and Larix leptolepis, and screened for the production of taxol on modified liquid medium for the first time. The presence of taxol was confirmed by spectroscopic and chromatographic methods of analysis. The amount of taxol produced by this fungus was quantified by high performance liquid chromatography. The maximum amount of fungal taxol production was recorded as 418 µg/l in the strain BKH 35. The production rate was increased to 8.36 x 103 fold than that found in the culture broth of earlier reported fungus, Taxomyces andreanae. The extracted fungal taxol also showed a strong cytotoxicity in the human cancer cells by apoptotic assay. All the ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2025501 Wed, 10 Dec 2008 05:00:00 +0100 2025501 http://www.medworm.com/index.php?rid=2012905&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080037 As abundant amount of porcine cartilage were discarded as waste in our daily life, it is necessary to find a new usage for it. We extracted polysaccharide from cartilage and performed in vitro and in vivo experiments in cancer cells using it. Mice breast cancer pulmonary metastasis model were set up and we tried to find the mechanism of metastasis inhibition by cartilage polysaccharide. Inhibitory rate of tumor weight and inhibitory rate of metastasis indicated that cartilage polysaccharide can obviously inhibit the metastasis of breast cancer cells. The contents of LNR1, αvβ3 integrin and MMP-9 showed significant difference between the mice treated with or without cartilage polysaccharide. Cartilage polysaccharide can inhibit the growth of MCF-7 cells but have little effect ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2012905 Thu, 04 Dec 2008 05:00:00 +0100 2012905 http://www.medworm.com/index.php?rid=2004075&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080220 Antibody-producing Chinese hamster ovary cells (CHO-DG44) were converted into cells producing antibodies with strongly enhanced antibody dependent cellular cytotoxicity (ADCC) by knocking down α1,6 fucosyltransferase (FuT8) via constitutive expression of shRNA against FuT8. After introduction of a FuT8 shRNA expression plasmid under the control of a U6 promoter CHO-DG44 clones with less than 5% residual FuT8 mRNA expression were isolated by selection for neomycin-resistance followed by l-NGFR-enrichment and selection for Lens culinaris agglutinin (LCA)- resistance . The CHO-DG44 clones identified produced highly afucosylated <IGF-1R> antibodies (up to 88%) that exhibited considerably enhanced ADCC compared to <IGF-1R> wildtype antibodies produced by parental CHO cells. A... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=2004075 Wed, 26 Nov 2008 05:00:00 +0100 2004075 http://www.medworm.com/index.php?rid=1988972&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080220 Antibody-producing Chinese hamster ovary cells (CHO-DG44) were converted into cells producing antibodies with strongly enhanced antibody dependent cellular cytotoxicity (ADCC) by knocking down α1,6 fucosyltransferase (FuT8) via constitutive expression of shRNA against FuT8. After introduction of a FuT8 shRNA expression plasmid under the control of a U6 promoter CHO-DG44 clones with less than 5% residual FuT8 mRNA expression were isolated by selection for neomycin-resistance followed by l-NGFR-enrichment and selection for Lens culinaris agglutinin (LCA)- resistance . The CHO-DG44 clones identified produced highly afucosylated antibodies (up to 88%) that exhibited considerably enhanced ADCC compared to wildtype antibodies produced by parental CHO cells. At the same time, antibody-prod... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1988972 Wed, 26 Nov 2008 05:00:00 +0100 1988972 http://www.medworm.com/index.php?rid=1979160&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080188 The objective of this study is to compare the performances of two urine sediment analyzers, UriSed and IQ200, with the KOVA® method for urine measurement, while evaluating the results in terms of similar parameters (cells or particles/LPF or HPF). The results indicate that the UriSed and IQ200 techniques were more reproducible (7.1-30.2%, 14.9-35.4%, respectively) than the manual technique (17.9-44.4%). Significant correlations were established among the three techniques in the evaluation of leukocytes, erythrocytes and epithelial cells. Although the UriSed, IQ200 and visual microscopic measurements were in agreement, confirmation of the results from automated methods by manual urine analyses is significantly useful, especially for pathological cases that were close to the limits of... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1979160 Fri, 21 Nov 2008 05:00:00 +0100 1979160 http://www.medworm.com/index.php?rid=1967544&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080084 Puroindolines are two small proteins so called for the presence of an hydrophobic tryptophan-rich domain. Associated to wheat starch granules in Triticum aestivum, puroindolines have been shown to be responsible for the softness of the wheat endosperm. Moreover, have been proved to possess bactericide and anti-fungal properties together with the capacity of forming very stable foams. All these features make puroindolines very attractive for medical, pharmaceutical and food industrial applications. The aim of this study was to explore a plant molecular farming approach for producing a recombinant puroindolines. Three specific recombinant constructs, aimed for the expression in the apoplast and chloroplast compartments, were prepared and used for transformation of Nicotiana tabacum cv BY-2 c... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1967544 Tue, 18 Nov 2008 05:00:00 +0100 1967544 http://www.medworm.com/index.php?rid=1891337&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080063 Addition of tags (as His-tags) is extremely helpful for the affinity-purification of recombinant proteins. In several cases these tags must be removed before performing functional and structural studies. The enzyme most frequently used to cleave tags of recombinant proteins is the Tobacco Etch Virus NIa protease (TEV-protease). The continuous production of this enzyme in soluble form is a quite expensive process and not easily accessible to many laboratories. Thus, an interesting alternative is the use of TEV-protease in an immobilized form, which may be reutilized several times. The main objective of the present study was to obtain a TEV-protease in an immobilized form, by covalent immobilization onto solid supports through selective use of different amino acid residues, lysine or cystein... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1891337 Tue, 21 Oct 2008 04:00:00 +0100 1891337 http://www.medworm.com/index.php?rid=1867571&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080133 Endogenous and adventitious virus removal by size-exclusion membrane filtration is a critical dedicated step in an overall viral clearance strategy employed by biologics manufacturers as required by industry regulators. However, the addition of impurities from virus spike preparations used in validation studies can significantly reduce filter capacity, resulting in an over-sized and suboptimal virus filtration step. The hydraulic filter performance and virus retention observed in conventional scaled-downed validation models may not necessarily represent performance observed during process development, nor be predictive of manufacturing performance. Using filter flow decay as a relevant processing endpoint, an alternative and more comprehensive approach to virus filter validation has been d... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1867571 Fri, 10 Oct 2008 04:00:00 +0100 1867571 http://www.medworm.com/index.php?rid=1867570&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080076 We have compared the accumulation of recombinant variable heavy chain portions (VHH) of camelid antibodies in a variety of subcellular compartments produced in planta. The VHH coding sequences were optimised for expression in Arabidopsis thaliana and placed individually or as fused, tandem, hetero dimers into synthetic plant organelle targeting cassettes designed to target the protein to either the cytoplasm, endoplasmic reticulum (ER), protein storage vacuole or chloroplast. Accumulation of individual VHHs was only detected in plants transformed with the ER targeting cassette whereas accumulation of the tandem VHHs was detected for all cassettes and was highest with the ER cassette [0.1-0.7 % (w/w) of total soluble proteins]. The ability of the plant produced tandem VHH to reduce TNF&#x03... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1867570 Fri, 10 Oct 2008 04:00:00 +0100 1867570 http://www.medworm.com/index.php?rid=1797261&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080020 Small cartilage defects treated with microfracture show comparable clinical results to those treated with autologous chondrocyte implantation (ACI). Unfortunately the regenerative tissue generated by microfracture treatment does not exhibit the structure and function of hyaline articular cartilage. Adult mesenchymal stem cells are supposed to be able to differentiate according to mechanical stimuli e.g. into chondrocytes thus generating hyaline cartilage. So far the used treatments such as the microfracture procedure are only able to induce mechanically insufficient fibrocartilage. The purpose of this study was to test the influence of a resorbable implant manufactured from PGLA-fleece (poly glycolic-co-lactic acid) in combination with microfracture in the weight-bearing area of the femora... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1797261 Tue, 16 Sep 2008 04:00:00 +0100 1797261 http://www.medworm.com/index.php?rid=1778405&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080088 The objective of this research was to evaluate antioxidant as well as antibacterial properties of secondary metabolites obtained from Drosera aliciae plants grown in vitro and examine the mechanism of their antimicrobial action. Bactericidal activity of extracts from D. aliciae as well as pure ramentaceone (naphthoquinone) present in this plant were examined against human pathogenic strains both resistant and susceptible to antibiotics. Chloroform extract proved to be more effective than methanol preparation against all of the tested strains except for Pseudomonas aeruginosa isolates with the lowest minimal bactericidal concentration (MBC) values in the case of Staphylococcus aureus (25-50 mg fresh weight ml-1). The influence of D. aliciae extracts and ramentaceone on the synthesis of DNA,... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1778405 Tue, 09 Sep 2008 04:00:00 +0100 1778405 http://www.medworm.com/index.php?rid=1763116&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080051 Detection of metastatic cells is clinically demanded to diagnose metastasis in the early stage and access the therapeutic response to anti-cancer drugs. We applied phage display technology to cultured cells with different metastasis potential and obtained four metastasis associated peptides. The association between peptides and metastatic cells were validated by ELISA as well as biosensor studies. The selected phage-peptides not only bind SW620, the metastatic cell against which the peptides were screened, but also able to capture breast cancer cells of high metastasis. The phage-peptide modified LAPS was able to distinguish metastatic cells from nonmetastatic cells and detect as few as 100 metastatic cells per mL of blood. Thus, LAPS modified with specific phage-peptides may be developed ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1763116 Thu, 04 Sep 2008 04:00:00 +0100 1763116 http://www.medworm.com/index.php?rid=1741669&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080057 This study would be helpful to optimize the expression of other therapeutic proteins by P.pastoris. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1741669 Fri, 29 Aug 2008 04:00:00 +0100 1741669 http://www.medworm.com/index.php?rid=1738275&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080054 Thymosin alpha 1(Tα1), an immune booster, plays an important role in the maturation, differentiation, and function of T cells, it also can activate the production of cytokines in dendritic cells (DCs). Tα1 is one of two thymosin proteins for potential future clinical applications. In order to express Tα1 protein in plant, we designed and synthesized the Tα1 gene according to the plant codon usage bias, and created a novel 4×Tα1 concatemer (four copies of Tα1 gene arranged end-to-end in tandem, designated 4×Tα1). Subsequently, a plant binary expression vector PG-pRD12-4×Tα1 was constructed and introduced into tomato via Agrobacterium tumefaciens mediated transformation. Through selection, 54 regenerated tomato plan... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1738275 Wed, 27 Aug 2008 04:00:00 +0100 1738275 http://www.medworm.com/index.php?rid=1704203&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080079 Thirty-nine microbes were screened for the ability to selectively N-demethylate (3R,5S,E)-7-(4-(4-fluorophenyl)-6-isopropyl-2-(methyl(1-methyl-1H-1,2,4-triazol-5-yl)aminopyrimidin-5-yl)-3,5-dihydroxyhept-6-enoic acid (I), a potential drug to lower blood cholesterol levels that act by inhibiting hydroxymethyl glutaryl CoA (HMG-Co A) reductase, a key enzyme involved in cholesterol biosynthesis. Two Streptomyces species were found to carry out the desired N-demethylation. Bioconversion of compound I to compound II by S. griseus ATCC 13273 gave 80% conversion at the end of the biotransformation process. After removal of cells, the product II, a key metabolite of I was adsorbed on to XAD-16 resin and product was recovered from resin in multi-gram level. (Source: Biotechnology and Applied Bioche... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1704203 Wed, 13 Aug 2008 04:00:00 +0100 1704203 http://www.medworm.com/index.php?rid=1681868&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080072 This study describes a quantitation assay method to a therapeutic human monoclonal antibody hMAb-1 that recognizes a cell surface protein employing an anti-idiotypic antibody (anti-ID) to hMAb-1 as an surrogate antigen in an immunoassay format using SPR technology. This assay is applicable for quantitation of hMAb-1 in process streams, final drug products quality control, as well as low concentration drug substances in IV bags. The surrogate nature of the anti-ID was confirmed by demonstrating that the anti-ID displaced the interaction between the hMAb-1 and its membrane antigen in a FACS titration test. The assay format involves first capturing hMAb-1 on the flow cell surface which then binds quantitatively to anti-ID in a mixture of increasing quantity of hMAb-1 in solution. An inverse d... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1681868 Tue, 05 Aug 2008 04:00:00 +0100 1681868 http://www.medworm.com/index.php?rid=1667823&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080060 The growing emergency due to the microorganisms drug resistance phenomenon, has pushed forward the search for new potential drugs alternative to those already in use. Plants represent a suitable source of new antifungal molecules, as they produce a series of defensive proteins. Among them are the Pathogenesis Related proteins (PRPs) shown effective in vitro against human pathogens. An optimized and established cell suspension culture of Zea mays was shown to constitutively secrete in the medium a series of PRPs comprising the antifungal protein zeamatin (P33679) with a final yield of around 3 mg per liter. The in vitro produced zeamatin possessed antifungal activity towards a Candida albicans clinical strain, activity comparable to the reported one for the same protein extracted from seeds... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1667823 Wed, 30 Jul 2008 04:00:00 +0100 1667823 http://www.medworm.com/index.php?rid=1654751&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080019 We describe secretory expression and immunogenicity of the recombinant Hepatitis A virus (HAV) VP1 from stably transformed Drosophila melanogaster S2 cells. Southern blot analysis indicated that transformed S2 cells contained multiple copies of the HAV VP1 gene in the genome. Recombinant VP1 was secreted into a culture medium with a molecular weight of 42 - 49 kDa. A maximum production level of 6.24 mg/l of recombinant VP1 was obtained in a T-flask culture of Drosophila S2 cells 5 days after induction with 0.5 mM CuSO4. The recombinant HAV VP1 protein elicited the production of specific IgA in the small intestine by oral immunization and production of specific IgG in the serum by intraperitoneal immunization. Our findings show that secretory recombinant VP1 from transformed Drosophila S2 c... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1654751 Fri, 25 Jul 2008 04:00:00 +0100 1654751 http://www.medworm.com/index.php?rid=1644928&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080073 Synopsis: As previously reported, a serine proteinase was purified from the snake venom of Deinagkistrodon acutus using a combination of affinity and ion exchange chromatography, and its high fibrinogen-clotting activity (2025 NIH unit/mg), indicated that this protein may have great potential as a drug to treat thrombolysis. In order to systemically determine the purified protein’s structure and activity, the protein was characterized using the following methods: mass spectrometry, isoelectric focusing, deglycosylation analysis, amino acid composition analysis, peptide mass fingerprinting, N-terminal amino acid sequencing, circular dichroism, hydrophobic site analysis, and bioactivity assays. In addition, a fluorescence probe was synthesized and conjugated to the protein in order to... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1644928 Tue, 22 Jul 2008 04:00:00 +0100 1644928 http://www.medworm.com/index.php?rid=1634236&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080074 A vaccine against Dengue virus must be able to induce an effective and equivalent immune response to the four viral serotypes; however, some studies have revealed that serotype 4 induce a weaker immune response than the others in tetravalent formulations. We have previously reported the protective capacity, in a viral encephalitis murine model, of fusion proteins P64k-envelope domain III of serotypes 1, 2 and 3. We also reported that the P64k protein can be used as a carrier in two different positions: the insertion following the first 45 amino acids and the fusion at the C-terminus. Considering the low immunogenicity described for the serotype 4, in this work we obtained a novel chimeric protein inserting two Dengue-4 envelope domains III in both sites of P64k (PD24), and hence increasing... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1634236 Thu, 17 Jul 2008 04:00:00 +0100 1634236 http://www.medworm.com/index.php?rid=1630257&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070269 Chimeric promoters contain DNA sequences from different promoters. Chimeric promoters are developed to increase the level of recombinant protein expression, precisely control transgene activity, or to escape homology-based gene silencing. Sets of chimeric promoters, each containing different lengths of DNA from the maize 27kDa gamma zein (27zn) endosperm-preferred promoter and the Globulin-1 (Glb1) embryo-preferred promoter were created and tested in a transient expression assay of green fluorescent protein (GFP). Promoter fragments with the highest activity were combined to create the chimeric promoter A27znGlb1. In the context of the chimeric promoter, the selected Glb1 promoter fragment was necessary and sufficient to activate expression in embryo tissue and was functionally equivalent ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1630257 Wed, 16 Jul 2008 04:00:00 +0100 1630257 http://www.medworm.com/index.php?rid=1630256&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080032 In this study we aimed for the generation of single chain antibody fragments (scFv) specific for the TNT-surrogate 2,4,6-trinitrophenyl (TNP) and their subsequent production as monoclonal avian IgY immunoglobulins providing improved assay performance. Therefore, we subjected a human synthetic scFv library to selection following different strategies. TNP-specific human antibody fragments could be identified, characterised for their primary structure and evaluated for production as soluble scFv in E. coli. Additionally, a murine TNP-specific antibody fragment was obtained from the hybridoma 11B3, however, the procaryotic expression level was found to be limited. To generate and evaluate immunoglobulin formats with superior characteristics, all recombinant antibody fragments then were convert... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1630256 Thu, 03 Jul 2008 04:00:00 +0100 1630256 http://www.medworm.com/index.php?rid=1595464&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080044 In this study, we attempted to enhance the sialylation of recombinant erythropoietin (EPO) in Chinese hamster ovary (CHO) cells. To enhance EPO sialylation, we introduced human α2,3-sialyltransferase (α2,3-ST) and CMP-sialic acid synthase (CMP-SAS) into recombinant human EPO-producing CHO cells. The sialylation of EPO was increased by the expression of α2,3-ST alone. Although the co-expression of α2,3-ST and CMP-SAS did not further increase sialylation, an increase in the intracellular pool of CMP-sialic acid was noted. Based on these observations, it was postulated that the transport capacity of CMP-sialic acid into the Golgi lumen was limited, thereby causing the reduced availability of CMP-sialic acid substrate for sialylation. Therefore, we co-expressed huma... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595464 Tue, 01 Jul 2008 04:00:00 +0100 1595464 http://www.medworm.com/index.php?rid=1595465&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080086 The purpose of this experimental study is to investigate the effects of garlic (Allium sativum L.) on the diabetic nephropathy and oxidative stress induced by streptozotocin (STZ) in rats. Male Sprague-Dawley rats were used and diabetes was induced by administering an intraperitoneal single injection of STZ (60 mg/kg). Administration of garlic, prepared as fresh garlic homogenate (FGH) significantly attenuated STZ-induced diabetic nephropathy as evaluated by assessment of serum glucose, insulin, total triglycerides (TG), total cholesterol (TC), and creatinine clearance (Ccr) in normal and STZ-induced diabetic rats. Urinary excretions of albumin, and N-acetyl-beta-D-glucosaminidase (NAG) were also reduced following the treatment with FGH. In addition, significant inhibition of thiobarbituri... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595465 Mon, 30 Jun 2008 04:00:00 +0100 1595465 http://www.medworm.com/index.php?rid=1595466&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070199 A nano-particle based electrochemical method for detection of Hepatitis-B virus DNA sequences has been developed. This method relies on the adsorption of amplified Hepatitis-B virus DNA strands onto probe coated paramagnetic particles and electrochemical detection of hybridized strands using Hanging Mercury Drop Electrode. For Hepatitis-B virus detection, a combination of dynamic DNA hybridization on transportable reactive surfaces, and label-free detection of DNA based on the electrochemical determination of adenines, was used. Separation of the hybridization area from the detection electrode eliminates non-specific adsorption of long DNA's and combining this method with dynamic synthesis of probe may open new flexible approaches for detection of other infectious agents by Lab-on-a-chip t... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595466 Mon, 23 Jun 2008 04:00:00 +0100 1595466 http://www.medworm.com/index.php?rid=1595467&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080005 The synthesized cDNA coding for acetylcholinesterase (AChE) was sub-cloned in pENTRTM/D-TOPO® plasmid and expressed using baculovirus expression vector and Sf9 cells as host. Purified enzyme (specific activity 36374 μmol.min-1.mg-1) was immobilized on preactivated perlite (a porous silica matrix) by silanization and glutaraldehyde treatment. Total enzyme immobilized was then measured and total and specific activity of immobilized AChE was compared to those of soluble enzyme. Using this perlite support not only resulted in a great amount of maintained immobilized enzyme activity (more than 70%, specific activity 26238 μmol.min-1.mg-1), but also significantly improved stability against temperature (8.7 and 17.7 fold at 50 and 60oC respectively), urea (2.7 fold) and aceto... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595467 Fri, 20 Jun 2008 04:00:00 +0100 1595467 http://www.medworm.com/index.php?rid=1595468&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080046 In conclusion, our results provide additional evidence that insertion of intronic sequences may be used to improve protein expression efficiency also in molecules that do not normally undergo any splicing process. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595468 Wed, 18 Jun 2008 04:00:00 +0100 1595468 http://www.medworm.com/index.php?rid=1595470&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080068 This study demonstrates that genetic engineering strategy of RNA interference is an effective means to increase artemisinin content in plants. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595470 Fri, 13 Jun 2008 04:00:00 +0100 1595470 http://www.medworm.com/index.php?rid=1595469&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070271 Conclusion, Proteins identified in this study are possible to have significant roles in the development of breast cancer in Malaysian Chinese patients in view of their consistent expression in most of the patients, although some of the proteins had not been detected in earlier studies that were mostly carried out in the Western countries. This observation suggests molecular mechanisms leading to breast cancer development in this region may not be identical with the western disease. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595469 Fri, 13 Jun 2008 04:00:00 +0100 1595469 http://www.medworm.com/index.php?rid=1595471&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080023 The monoterpene d-limonene has been shown to have cancer prevention and cancer therapeutic activities in vitro and in vivo. Unlike plants, animals are unable to synthesize limonene de novo, and so utilize limonene through dietary sources. Here we established transgenic NIH3T3 cells that produce limonene by introducing the d-limonene synthase gene obtained from the plant Schizonepeta tenuifolia. Apoptosis was not observed in the limonene-producing cells probably due to low levels of limonene, although exogenously applied limonene at high concentration was proven to induce G1 arrest or apoptosis in various cells in vitro. A concomitant increase in the level of apoptosis-related protein Bcl-2 and decreases in the levels of Bad and phosphorylated JNK were observed in limonene-producing cells. ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595471 Wed, 11 Jun 2008 04:00:00 +0100 1595471 http://www.medworm.com/index.php?rid=1595472&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080041 Amyloglucosidase from Rhizopus mold and β-glucosidase from sweet almond were employed for the preparation of phenolic and vitamin glycosides of vanillin, N-vanillyl-nonanamide, DL-dopa, dopamine, curcumin, α-tocopherol (vitamin E), pyridoxine (vitamin B6), ergocalciferol (vitamin D2), thiamin (B1) and riboflavin (B2). About 20 enzymatically prepared phenolic and vitamin glycosides were subjected to Angiotensin Converting Enzyme (ACE) inhibition activity measurements and 14 glycosides were tested for antioxidant activities. Both phenolic and vitamin glycosides exhibited IC50 values for ACE inhibition in the 0.52 ± 0.03 mM to 3.33 ± 0.17 mM range and antioxidant activities ranging from 0.8 ± 0.04 mM to 1.18 ± 0.06 mM. Comparable ACE inhibition values... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595472 Fri, 06 Jun 2008 04:00:00 +0100 1595472 http://www.medworm.com/index.php?rid=1595473&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070187 In this study, a plasmid containing genes of apo-ApcA and chromophore synthetases(HO1 and PcyA) was constructed and expressed in E. coli. The result shows that APC α-subunit (holo-ApcA) can be synthesized by autocatalysis in E. coli. Recombinant holo-ApcA showed the same spectral and fluorescent properties as phycocyanin, and could serve as a good substitute of native phycocyanin for fluorescent tag. Moreover, recombinant ApcA can inhibit hydroxyl and peroxyl radicals more strongly than holo-ApcA and native APC. The EC50 values were 296.4±22.4µg/mL against hydroxyl and 38.5±2.6µg/mL against peroxyl radicals. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595473 Thu, 05 Jun 2008 04:00:00 +0100 1595473 http://www.medworm.com/index.php?rid=1595474&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070264 In conclusion, this study indicates that NADPH oxidase induced ROS generation activates Fas mediated death pathway. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595474 Wed, 21 May 2008 04:00:00 +0100 1595474 http://www.medworm.com/index.php?rid=1595475&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070267 Recombinant human granulocyte colony stimulating factor (rhG-CSF) was expressed in Pichia pastoris under the control of the AOX1 promoter. The production of rhG-CSF was induced by switching from growth on glycerol to growth on methanol. In the induction phase, methanol feed rate had a significant effect on the specific expression rate of rhG-CSF. A constant feed rate of 16 ml l-1 h-1 was found to be optimum for a high specific expression rate of rhG-CSF (0.058 mg g DCW-1 h-1). Under this condition, a maximum concentration of 300 mg l-1 of rhG-CSF and the expression yield of 0.6 mg rhG-CSF g-methanol-1 were attained. However, the secreted rhG-CSF was shown to exist as aggregates in the culture broth due to hydrophobic interaction. To prevent undesirable protein aggregation, presences of add... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595475 Wed, 14 May 2008 04:00:00 +0100 1595475 http://www.medworm.com/index.php?rid=1595476&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070276 We have previously shown the cyanobacterium Anabaena sp. PCC 7120 to be an attractive host for the production of isotopically labeled recombinant proteins using the nitrate-inducible nir expression system. However, the expression of toxic proteins such as oncoproteins proved to be difficult, as expression levels decreased shortly after induction while growth continued. To overcome this limitation, we have developed a method of auto-induction of the nir promoter, in which cells are grown to high cell density in a bioreactor in the presence of ammonium and nitrate. Since ammonium is the preferred nitrogen source and acts as a repressor of the nir promoter, induction occurs only when the ammonium had been depleted. Using this novel auto-induction method, both oncoproteins E6 and gankyrin were... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595476 Mon, 12 May 2008 04:00:00 +0100 1595476 http://www.medworm.com/index.php?rid=1595477&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080013 The gene encoding Psychrobacter sp. HJ147 uracil-DNA glycosylase (Psp HJ147 UDG) was cloned and sequenced. The gene consists of 735 bp for coding a protein with 244 amino acid residues. The deduced amino acid sequence of Psp HJ147 UDG showed a high similarity to Psychrobacter articus, Psychrobacter cryohalolentis K5, and Psychrobacter sp. PRwf-1. The PCR amplified Psp HJ147 UDG gene was expressed under the control of the T7lac promoter on pTYB1 in Escherichia coli BL21 (DE3). The expressed enzyme was purified by one step using the IMPACT-CN system. The optimum pH and temperature of the purified enzyme were 7.0-7.5 and 20-25°C, respectively. The optimum NaCl and KCl concentration of the purified enzyme ranged from 50-75 mM. The half-life of the enzyme at 50°C was approximately 45 ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595477 Fri, 09 May 2008 04:00:00 +0100 1595477 http://www.medworm.com/index.php?rid=1595478&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070245 In this study a new expression system, E. coli strain Rosetta 2(DE3), was used for high-level expression of recombinant PA (rPA) whose gene contains 66 rare E. coli codons (9.0%). The rPA-formed inclusion bodies were washed by Triton X-100 and 2 M urea and solubilized in 5 M urea, followed by a 60% ammonium sulfate precipitation. Finally, the untagged rPA was efficiently and rapidly purified by single-step hydrophobic interaction chromatography using Phenyl Sepharose High Performance on an AKTA Purifier 10 system. The yield was approximately 13 mg highly pure (<99%) biologically active rPA per liter of culture, which can be used for the detection of anthrax and as a potential component of a vaccine against anthrax. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595478 Thu, 17 Apr 2008 04:00:00 +0100 1595478 http://www.medworm.com/index.php?rid=1595479&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080028 Various approaches for removal of high abundant components in body fluids are currently available. While most methods are constructed for plasma depletion, there is a need for body fluid specific strategies. The aim of this project was to design an affinity matrix suitable for the depletion of high-abundant proteins in cerebrospinal fluid (CSF). Hence, molecules with specific affinity towards proteins with high concentration in CSF were desired. Affibody molecules are specific binders of small size that have shown high stability under various conditions and are therefore good candidates for such a matrix. The protein composition in CSF resembles that in plasma. However, 20% of the proteins are brain-derived and therefore present at higher proportions in CSF than in plasma, while larger pla... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595479 Tue, 15 Apr 2008 04:00:00 +0100 1595479 http://www.medworm.com/index.php?rid=1595480&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070256 This group has developed a non-biodegradable nanocomposite based on polyhedral oligomeric silsesquioxanes (POSS) nano-cages with poly(carbonate-urea)urethane and previous studies have shown good cell compatibility and antithrombogenic properties. The latest biodegradable formulation is a POSS modified poly(caprolactone/carbonate)urethane/urea containing 80% caprolactone with trade name UCL-NanoBioTM. The direct effect of the polymer on cells was investigated by seeding stem cells onto circular discs of the polymer in 24-well plates; these discs were prepared mainly by electrohydrodynamic jetting. To assess the indirect effect of the polymer, varying concentrations of the polymer powder was added to cell culture media and left on a shaker for ten days. The precipitate was then removed and t... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595480 Thu, 10 Apr 2008 04:00:00 +0100 1595480 http://www.medworm.com/index.php?rid=1595481&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080015 An affinity matrix containing the antimalarial drug target Plasmepsin II (Plm II) as ligand was generated. This enzyme belongs to the family of Plasmodium aspartic proteinases, known as Plasmepsins. The procedure established to obtain the support has two steps: the immobilization of the recombinant pro-enzyme of Plm II to NHS-Sepharose and the activation of the immobilized enzyme by incubating at pH 4.4 and 37°C. The coupling reaction showed a high percentage of immobilization (95.5 %) and the matrices obtained had an average of 4.3 mg of protein per ml of gel. The activated matrices, but not the inactive ones, were able to hydrolyse two different chromogenic peptide substrates and haemoglobin. This ability was completely blocked by the addition of the general aspartic proteinase inhi... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595481 Wed, 09 Apr 2008 04:00:00 +0100 1595481 http://www.medworm.com/index.php?rid=1595482&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070260 Well-characterized derivatives of Escherichia coli K12 such as DH5{alpha} are commonly-used host strains for plasmid DNA production. Due to the prospective clinical demand for large quantities of plasmid DNA for gene therapy and DNA vaccination, existing plasmid production processes need to be optimized to attain higher plasmid yields. To date, nearly all production optimization efforts are focused on media or fermentation process design. Other than the simple empirical evaluation of available host strains, there is a lack of systematic effort to engineer these host strains for improved plasmid DNA production. In view of that, we engineered DH5{alpha} wildtype (WT) cells carrying a DNA vaccine plasmid by knocking out the FruR (also known as Cra) global regulator gene and evaluated the grow... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595482 Wed, 02 Apr 2008 04:00:00 +0100 1595482 http://www.medworm.com/index.php?rid=1595483&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080018 Pseudomonas cepacia lipase-catalyzed preferential acylation of the secondary hydroxyl group of floxuridine (FUdR) with vinyl crotonate was carried out in spite of the presence of the primary hydroxyl group and 3'-O-crotonyl-floxuridine was prepared successfully for the first time. The isomerization of the double bond of crotonate, which occurs in conventional organic synthesis, could be effectively avoided during the enzymatic acylation. The influences of several key factors such as reaction media, initial water activity ({alpha}w), molar ratio of vinyl crotonate to FUdR, FUdR concentration and reaction temperature on the reaction were examined. Under the optimized reaction conditions, the initial reaction rate, substrate conversion and 3'-regioselectivity of the reaction were as high as 2... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595483 Fri, 28 Mar 2008 04:00:00 +0100 1595483 http://www.medworm.com/index.php?rid=1595484&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070210 We have developed a novel protocol for directional cloning of PCR products into any vector. The target sequence is amplified in two parallel asymmetric PCRs using specially but simply designed primers. Two single-stranded products are produced and annealed to form a double-stranded DNA fragment bearing overhangs at both ends that correspond to the restriction overhangs of certain restriction enzymes. The fragment can then be cloned into a certain vector previously treated with the corresponding enzymes without restriction of the inserted fragment. Compared to previously published protocols, the procedure described in this article is highly efficient and independent of the restriction sites of the insert and is therefore applicable to molecular biology and biotechnology studies. (Source: Bi... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595484 Wed, 19 Mar 2008 04:00:00 +0100 1595484 http://www.medworm.com/index.php?rid=1595485&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070249 This report presents a procedure to obtain and purify recombinant human VECA expressed in Escherichia coli as a fusion protein, in which human VECA cDNA is linked to pQE30 expression vector with six histidine residues. The purified protein was used to raise anti-human VECA polyclonal antibodies, which were suitable to detect the presence of VECA in cells, culture medium and tissues by immunoblotting and immunohistochemistry. As we known, this is the first report dealing with the protein expression and polyclonal antibodies production of human VECA. In addition, this communication reports for the first time the positive identification of VECA in human at the protein and subcellular level, and the first experimental verification that VECA was indeed a secreted protein. The prepared anti-huma... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595485 Fri, 14 Mar 2008 04:00:00 +0100 1595485 http://www.medworm.com/index.php?rid=1595486&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070174 The effect of bacterial cell centrifugation and handling on the initial stages of plasmid processing was investigated. E. coli cells containing either a 6 or 20 kb plasmid were grown in 75 and 450 L bioreactors and the process yield of the early recovery stages was characterised in terms of supercoiled plasmid DNA (SC pDNA) recovered. In all cases the cells were totally recovered using either a continuous-feed, intermittent solids-discharge, disk-stack centrifuge or a continuous-feed, batch-discharge, solid-bowl centrifuge. The cells were then either processed immediately or stored frozen. The centrifugation method considerably affected the yield of SC pDNA with evidence that the intermittent discharge of the cells from a centrifuge operating at high speed led to a sediment containing lyse... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595486 Mon, 03 Mar 2008 05:00:00 +0100 1595486 http://www.medworm.com/index.php?rid=1595487&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070169 Two cell-binding domains from fibroblast growth factor (FGF)-2 were identified to increase the cell attachment and osteoblastic differentiation. Two synthetic peptides derived from FGF-2, the residues 36 to 41 (F36, PDGRVD) and 77 to 83 (F77, KEDGRLL), were prepared and their N-terminals further modified for ease of surface immobilization. Chitosan membranes were used in our study as mechanical supportive biomaterials for peptide immobilization. Peptides could be stably immobilized onto the surface of chitosan membranes. The adhesion of mesenchymal stem cells to the peptides (F36 and F77) immobilized chitosan membrane was increased in a dose dependent manner and completely inhibited by soluble RGD and anti-integrin antibody, indicating the existence of an interaction between F36/F77 and in... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595487 Thu, 28 Feb 2008 05:00:00 +0100 1595487 http://www.medworm.com/index.php?rid=1595488&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080004 Salvia miltiorrhiza Bunge (Lamiaceae) is a valuable Chinese herbal plant, and its rhizome is the useful part for medicine, known as Danshen in Chinese because of its characteristic red pigment. The red pigment in S. miltiorrhiza roots is mainly composed of numerous diterpenoid tanshinones, as the major bioactive ingredients of the herb. In plants, diterpenes are synthesized through the 2-C2-methyl2-d2-erythritol 42-phosphate (MEP) pathway in the plastids, and 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) is an enzyme catalyzing the first step of the MEP pathway. In this work, a full-length cDNA encoding DXR (GenBank accession No. DQ991431) was cloned from the hairy roots of S. miltiorrhiza in culture. The enzyme activity of DXR protein was verified by complementation of an Escheric... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595488 Wed, 27 Feb 2008 05:00:00 +0100 1595488 http://www.medworm.com/index.php?rid=1595491&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070242 The apoptosis effects of natural and synthetic diallyl disulfide (DADS) on human breast cancer MCF-7 cells were investigated in vitro. The fluorouracil and cyclophosphamide were used as control. After MCF-7 cells were treated with drugs, cell viability, morphological change, apoptosis, and the change of cell cycle were measured. These results indicated that synthetic and natural DADS had similar cytotoxicity on human breast cancer MCF-7 cells and showed a dose-dependent and time-dependent inhibitory effect on MCF-7 cells. The morphologic observation and flow cytometer results showed that these four drugs induced MCF-7 cells apoptosis in different degree. The apoptosis effects of synthetic diallyl disulfide and natural DADS were superior to that of 5-Fu and CTX. (Source: Biotechnology and A... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595491 Thu, 21 Feb 2008 05:00:00 +0100 1595491 http://www.medworm.com/index.php?rid=1595490&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070197 The gene transfer mediated by chitosan in a cystic fibrosis bronchial epithelial cell line (CFBE41o-) and a human embryonic kidney cell line (HEK) has been evaluated. Polyplexes based on chitosan and polyethylenimine (PEI) using a luciferase reporter plasmid shows that the transfection efficacy of polyplexes in the CFBE41o- cell line was poor compared to a human embryonic kidney cell line. In the highly differentiated cystic fibrosis bronchial epithelial cell line the narrow size distributed chitosan shows enhanced transfection at a low pH, compared to PEI. The enhanced transfection at lower pH could be a result of damage to the cell surface or changes in the cell surface charge leading to better penetration of the cell membrane. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595490 Thu, 21 Feb 2008 05:00:00 +0100 1595490 http://www.medworm.com/index.php?rid=1595489&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070212 Schwann cells are essential facilitators of peripheral nerve regeneration following injury as they provide physical support and guidance. In vitro these supporting cells are slow growing, hence not well suited to a tissue engineering approach to nerve repair. We have differentiated rat bone marrow-derived mesenchymal stem cells into Schwann cell-like cells using a cocktail of growth factors including glial growth factor-2. Qualitative reverse transcriptase-polymerase chain reaction, western blotting and immunocytochemistry approaches were used to investigate the mRNA transcript levels and protein expression of glial cell markers and neurotrophic factors in differentiated mesenchymal stem cells compared to the levels found in Schwann cells (positive control). The results showed differentiat... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595489 Thu, 21 Feb 2008 05:00:00 +0100 1595489 http://www.medworm.com/index.php?rid=1595492&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070201 In this study, a new cell culture method using a low calcium medium supplemented with N-acetyl-L-cysteine and L-ascorbic acid-2-phosphate (the PM2 medium) was developed to grow porcine adipose tissue-derived stem cells (pASCs). The pASCs developed using the new medium showed fast growth rate and high proliferation potential as measured by cumulative population doubling level (cpdl=55) that was significantly higher than those reported for ASCs in literature. These pASCs lacked gap junctional intercellular communication, and were capable of differentiation into three mesodermal lineages (i.e. adipocytes, osteoblasts and chondrocytes) and ectodermal lineage (i.e. neural cells). Surprisingly, the osteogenic ability but not adipogenesis was found to increase dramatically with increasing passage... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595492 Mon, 18 Feb 2008 05:00:00 +0100 1595492 http://www.medworm.com/index.php?rid=1595493&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070141 Peroxidase POX1 isoenzyme was purified from garlic bulb (Allium sativum L.) by ammonium sulfate precipitation, gel filtration and anion exchange chromatography. Native-PAGE profile showed two isoforms designated POX1A and POX1B. POX1B seems to be more attractive for biosensor design since its apparent Km for H2O2 is lower than that of POX1A. In addition of its storage and operational stability, POX1B was found to be highly stable vs. temperature since almost 70 % of its activity is conserved at 60°C, whereas full activity is retained at 50°C and 40°C during 40 min. The optimum pH was around 5 and the optimum temperature was 30°C. However, gelatin was used as a matrix for enzyme immobilization on gold electrode surface and electrochemical measurements were achieved by cy... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595493 Wed, 13 Feb 2008 05:00:00 +0100 1595493 http://www.medworm.com/index.php?rid=1595495&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070178 c-Jun is a highly oncogenic transcription factor involved in the development of different types of cancers. In this work we have generated c-Jun binding affinity proteins from a phage-displayed library of so-called Affibody ligands, developed by combinatorial engineering of a non-immunoglobulin based scaffold protein. Homo-dimeric c-Jun protein was recombinantly produced in Escherichia coli and prior to selection, the quality of the target protein was investigated by binding analyses showing specific binding to a double stranded DNA hairpin construct containing a c-Jun response element but not to a control sequence. Isolated Affibody variants from the phage selection were expressed in Escherichia coli, purified by affinity chromatography and their interaction with c-Jun was analyzed. In bi... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595495 Mon, 11 Feb 2008 05:00:00 +0100 1595495 http://www.medworm.com/index.php?rid=1595494&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070213 Embryonic stem cells efficiently silence retrovirus transgene expression. To help solve this problem, retroviruses have been developed that are more resistant to silencing, such as retroviruses derived from the murine stem cell virus (MSCV). A complimentary approach to increasing transgene expression might be to increase the number of integrated transgenes. To test this approach, we formed polymer complexes with MSCV-derived ecotropic retroviruses, concentrated them up to 40-fold, and transduced two different murine embryonic stem cell lines, and a mouse fibroblast cell line as a control. The number of integrated transgenes increased more than 50-fold in the embryonic stem cell lines, yet, surprisingly, transgene expression did not increase. Interestingly, the embryonic stem cells had sign... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595494 Mon, 11 Feb 2008 05:00:00 +0100 1595494 http://www.medworm.com/index.php?rid=1595496&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20080007 Fullerene C60 has been recognized an efficient free radical scavenger. Due to the high antioxidative capacity, C60 and its derivates have a great potential for the applications in biological systems where prevention of oxidative cell damage is desirable. However, poor solubility of native C60 in water represents a major drawback for its use in biological systems. In order to increase the efficiency of deliverance of fullerenes to target tissues, it is of great interest to enhance their water solubility by developing hydrophilic organo-derivatives of C60 with retained antioxidative properties, and/or by encapsulating fullerenes in biocompatible liposomes. In the present study, using EPR spin-trapping and spin-labelling techniques, we investigated antioxidative capacities of fullerene C60 an... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595496 Fri, 08 Feb 2008 05:00:00 +0100 1595496 http://www.medworm.com/index.php?rid=1595497&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070243 Terminalia arjuna, is a medicinal plant which possess anticancer activity. An endophytic fungus Pestalotiopsis terminaliae was isolated from the fresh, healthy leaves of this medicinal plant was screened for the production of taxol, an anticancer drug in artificial culture medium and analyzed chromatographically and spectrometrically. The amount of taxol produced by the fungus was found to be 211.1 µg/L, thus the fungus can serve as a potential material for fungus engineering to improve the production of taxol. This fungal taxol extracted from the organic extract of this fungal culture, had strong cytotoxic activity towards BT 220, H116, Int 407, HL 251 and HLK 210 human cancer cells in vitro, tested by Apoptotic assay. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595497 Wed, 06 Feb 2008 05:00:00 +0100 1595497 http://www.medworm.com/index.php?rid=1595499&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070205 Human lysozyme (hLM) has important application potential as a safely administered drug and food additive for human being in the near future. To achieve secreted recombinant human lysozyme (rhLM) from yeast Pichia pastoris, human serum albumin (HSA) signal peptide was employed to direct secreted expression. Based on the vector pPIC3.5K, an over-expression vector pPIC3.5k-hLM carrying the strong promoter AOX1, HSA signal peptide, enterokinase recognition motif, lysozyme gene and other necessary genetic segments was constructed and followed by a series of genetic manipulations as described in the materials and methods. A positive colony was picked to test its expression pattern. The purpose protein was obtained from the supernatant which exhibited a gradual enrichment with the induction time ... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595499 Tue, 05 Feb 2008 05:00:00 +0100 1595499 http://www.medworm.com/index.php?rid=1595498&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070219 The conformation and dynamics of double-stranded DNA molecules in a pressure-driven flow through sharp/gradual converging(contraction half)-diverging(expansion half) square micro-channels with a contraction/expansion ratio of 4:1/1:4 are examined through the use of fluorescent labeled {lambda}-DNA at 2.2 {Less-Than Or Equal To} De {Less-Than Or Equal To} 30.7. Both the diffusion and stretching of individual DNA molecules and their local flow velocity are visualized, recorded and measured with micro-particle image velocimetry (MPIV) and confocal laser scanning microscopy (CLSM). The onset of the coil-stretch transition in DNA molecules and their time-dependent velocity in the elongational flow are determined at the micro-scale. Velocity distribution is measured via MPIV through orange fluor... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595498 Tue, 05 Feb 2008 05:00:00 +0100 1595498 http://www.medworm.com/index.php?rid=1595502&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070238 Previously, we have developed a SNP genotyping method, MagSNiPer. In this paper, we show development of an automated system for MagSNiPer, MagSNiPer Station, and its application for quantitative discrimination of Dehalococcoides species, which perform anaerobic dechlorination of chloroethenes. MagSNiPer Station is equipped with a thermal cycler, a tip stand, a microtiter plate automated stacker, an eight-channel tip dispenser, a magnetic separation unit for Magtration technology, and a chemiluminescence detector. It can automatically perform all processes required for SNPs genotyping by MagSNiPer. A primer was designed for discriminating single nucleotide difference between 16S rRNA genes of Dehalococcoides ethenogenes and Dehalococcoides BAV1. Chemiluminescence intensities for the 16S rRN... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595502 Mon, 04 Feb 2008 05:00:00 +0100 1595502 http://www.medworm.com/index.php?rid=1595501&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070123 In this study, a precursor tetrapeptide Bz-RGDS-NH2 of cell adhesive peptide RGDS was synthesized by a novel route. First of all, the precursor tripeptide Gly-Asp-Ser-NH2 (GDS-NH2) was synthesized by a chemical method only using aspartic acid and serine at gram scale in four steps. The linkage of the fourth amino acid Bz-Arg-OEt to GDS-NH2 was completed by enzymatic method under kinetic control in water-miscible organic media. An industrial alkaline protease alcalase with wide substrate specificity was used as the catalyst. The effects of organic solvents, pH value, reaction temperature, water content and molar ratio of substrates on the yield of Bz-RGDS-NH2 synthesis were examined. The optimum reaction conditions are pH 10.0, 35°C, 8h, in acetonitrile/ Na2CO3-NaHCO3 buffer system (93... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595501 Mon, 04 Feb 2008 05:00:00 +0100 1595501 http://www.medworm.com/index.php?rid=1595500&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070190 In this study, several vector-based siRNAs of hGDH were constructed and directly expressed intracellularly from a plasmid DNA. Using immunoblotting method, it was confirmed that hGDH expressions were knockdown by most of phGDH-siRNAs in BE(2)C human neuroblastoma cells. RT-PCR analysis showed that mRNA level also was decreased like as hGDH protein level. TUNEL assay and DNA fragmentation assay after 48 h co-transfection phGDH-siRNAs revealed that inhibition of hGDH expression induced apoptotic condition in BE(2)C human neuroblastoma cells and activated phospho-ERK1/2. It is shown that inhibition of hGDH expression by siRNA are related with apoptosis in neuronal cells. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595500 Mon, 04 Feb 2008 05:00:00 +0100 1595500 http://www.medworm.com/index.php?rid=1595503&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070182 In conclusion, recombinant fowlpox virus FPCoE1 is able to induce anti-HCV immune response in mice and monkeys. This ability could be rationally employed to develop effective strategies against HCV infection by using FPCoE1 in combination with other vaccine candidates or antiviral treatments. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595503 Thu, 24 Jan 2008 05:00:00 +0100 1595503 http://www.medworm.com/index.php?rid=1595504&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070200 Common rue (Ruta graveolens L.) accumulates various types of secondary metabolites, such as coumarins furanocoumarins, acridone and quinolone alkaloids, and flavonoids. Elicitation is a tool extensively used for enhancing secondary metabolite yields. Chitin and chitosan are examples of elicitors inducing phytoalexin accumulation in plant tissue. This paper present the application of chitin and chitosan as potential elicitors of the secondary metabolites accumulations in Ruta graveolens shoots cultivated in vitro. The simple coumarins, linear furanocoumarins, dihydrofuranocoumarins and furoquinolone alkaloids biosynthesized in the presence of chitin and chitosan were isolated, separated and identified. There was a significant increase in the growth rate of Ruta graveolens shoots in the pres... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595504 Tue, 22 Jan 2008 05:00:00 +0100 1595504 http://www.medworm.com/index.php?rid=1595505&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070255 Polyphenols including flavonoids are the major components of the extracts from aceraceous plant. They possess remarkable antibacterial and antitumor activity. Our study focused on whether the inhibition of bacterial type II fatty acid synthesis system is the mechanism for the antibacterial effect of the related plant polyphenol. The extracts by different solvents and the related pure compound, 1,2,3,4,6-Penta-O-galloyl-beta-D-glucose, potently inhibited the FabG reductase steps in the fatty acid elongation cycle with the IC50 values between 0.9 and 7.2 µg/ml. The EtOAc extract appeared to inhibit FabG reductase in a mixed manner with NADPH, whereas PGG inhibits the enzyme competitively with NADPH, demonstrating that they interfered with the cofactor binding to the enzyme. Gram-positiv... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595505 Mon, 21 Jan 2008 05:00:00 +0100 1595505 http://www.medworm.com/index.php?rid=1595506&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070228 This paper describes the application of Global Sensitivity Analysis (GSA) techniques to mathematical models of bioprocesses in order to rank inputs such as feed titres, flowrates and matrix capacities for the relative influence that each exerts upon outputs such as yield or throughput. GSA enables quantification of both the impact of individual variables on process outputs as well as their interactions. These data highlight those attributes of a bioprocess which offer the greatest potential for achieving manufacturing improvements. Whereas previous GSA studies have been limited to individual unit operations, this paper extends the treatment to an entire downstream process and illustrates its utility by application to the production of a FAB-based rattlesnake anti-venom called CroFabTM (Pro... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595506 Fri, 18 Jan 2008 05:00:00 +0100 1595506 http://www.medworm.com/index.php?rid=1595507&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070227 Antitumor lipopeptide biosurfactant purified from Bacillus natto TK-1 was able to inhibit the proliferation of MCF-7 (human breast cancer cell line) cancer cells in a dose- and time-dependent manner. The activity of LDH (lactate dehydrogenase) release showed no significant difference between MCF-7 cells treated with lipopeptide and without. The antitumor activity of lipopeptide in MCF-7 cells was associated with cell apoptosis determined by typical morphological changes and sub-G1 peak in cell phase distribution. The cell cycle was arrested at G2/M phase. In addition, the caspases activity assay revealed that lipopeptide-induced apoptosis in MCF-7 cells was associated with caspase-3. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595507 Wed, 16 Jan 2008 05:00:00 +0100 1595507 http://www.medworm.com/index.php?rid=1595508&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070223 An in vitro reproductive cell-based toxicity assay was developed using the murine Leydig tumour cell line (MLTC-1) in order to examine the reproductive toxicity of two novel nanopharmaceutical compounds, glycol mono allyl ether and poly (ethylene glycol) octa-functionalized polyhedral oligomeric sisesquioxane. Three commonly used cytotoxicity assays; the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide), MTS (3-(4,5-dimethylthiazol-2-yl)5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium bromide) and crystal violet assays were compared, and the MTT assay proved to be the most accurate and reproducible for the MLTC-1 cell line. The doubling rate of the MLTC-1 cells was 30 ± 3.5hrs, optimal seeding density for the MTT assay was 20,000cells/well and the optimise... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595508 Wed, 02 Jan 2008 05:00:00 +0100 1595508 http://www.medworm.com/index.php?rid=1595509&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070173 Cytochrome P450 (P450 or CYP) enzymes catalyze the monooxygenation of a wide range of compounds such as steroids, fatty acids, vitamins and drugs. Here we show a system for bioconverting diverse compounds (flavanone,dehydroepiandrosterone and 7-ethoxycomarine) using P450 species expressed in Escherichia coli. We first expressed 4 P450 species such as rabbit CYP2B, fly CYP317A, rat CYP3A23 and mouse CYP2J5, respectively. Next, we added substrates directly to the incubation medium. The resulting metabolites were extracted and analyzed by high-performance liquid chromatography (HPLC) and spectrofluorometer. The first substrate, 7-ethoxycoumarin, was deethylated by CYP2B; CYP2J5 and CYP3A23 showed weak activity, and CYP317A had no activity for 7-ethoxycoumarin. We next used flavanone, a flavon... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595509 Thu, 06 Dec 2007 05:00:00 +0100 1595509 http://www.medworm.com/index.php?rid=1595510&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070096 Fructus Lycii (Gouqizi) is well-known in Chinese herbal medicine for its restorative function of benefiting the liver and the kidney, replenishing vital essence and improving eyesight. However, ten species and varieties of Lycium are found to be substitutes or adulterants of L. barbarum in the commercial market in Hong Kong and China. L. barbarum cv. 'Tianjinense' and L. chinense var. potaninii are the most common examples. It is difficult to differentiate among the Lycium species by traditional morphological and histological analysis. An easy and reliable approach based on SCAR (Sequence Characterized Amplified Region) analysis was developed in this study to differentiate L. barbarum from other Lycium species. Two characteristic bands of about 700 and 650 bp were detected on the RAPD (Ran... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595510 Wed, 05 Dec 2007 05:00:00 +0100 1595510 http://www.medworm.com/index.php?rid=1595511&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070186 A Burkholderia cepacia strain ATCC 25609, which had been isolated from the bronchial washings of a cystic fibrosis patient was used to produce lipase. The presence of sodium alginate at an optimum concentration of 8 mg ml-1 in the growth medium nearly doubled the production of extracellular lipase activity. The enzyme could be purified with 38 fold purification and 96% activity recovery using a two-step purification protocol. The molecular weight of the purified lipase determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was shown to be 28 kDa. The purified enzyme showed pH optimum at pH 9 and it was stable upto 12 h at pH 9 and 10. The enzyme has temperature optimum at 40 °C and its half-lives were 54 min and 46 min at 50 °C and 60 °C respectiv... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595511 Tue, 04 Dec 2007 05:00:00 +0100 1595511 http://www.medworm.com/index.php?rid=1595512&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070229 Suppression of tumor necrosis factor {alpha} activity is widely considered to be among the most efficient treatments available for chronic inflammatory diseases. Here, a bivalent single chain Fv fragment, named TNF-BAb, was engineered by fusing two anti-TNF{alpha} single chain Fv fragments in tandem via a long and flexible linking peptide derived from human serum albumin, and produced in functional form from E. coli inclusion bodies. The bioactivity assays demonstrated that TNF-BAb gained enormously in avidity and showed a much stronger ability to inhibit the biological action of TNF{alpha}, indicating that TNF-BAb may become a good candidate for anti-TNF{alpha} therapy. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595512 Fri, 30 Nov 2007 05:00:00 +0100 1595512 http://www.medworm.com/index.php?rid=1595513&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070225 Staphylokinase (Sak), produced by lysogenic strains of Staphylococcus aureus, can convert plasminogen into its proteolytic form plasmin, and thus is widely used to dissolve pathologic clots in clinical applications. Here we report a novel approach to produce recombinant staphylokinase(r-Sak) using an engineered Escherichia coli expression system. The expression plasmid was constructed by placing the staphylokinase gene into the expression vector pET32 (a), resulting in the expression of 35% fusion protein. And subsequently a rapid and simple chromatographic procedure is developed for the large-scale purification of therapeutic-grade r-Sak from Escherichia coli, which includes Ni2+ affinity chromatography, ultrafiltration and Q-Sepharose Fast Flow chromatography. This method led to the prod... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595513 Tue, 30 Oct 2007 04:00:00 +0100 1595513 http://www.medworm.com/index.php?rid=1595514&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070145 This study has independently validated the benefits automation brings to the microarray hybridization process and highlights the differences between the instruments examined. We further comment on higher quality of spot morphology when hybridization is performed at a lower temperature in combination with our buffer of choice. (Source: Biotechnology and Applied Biochemistry) Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595514 Mon, 22 Oct 2007 04:00:00 +0100 1595514 http://www.medworm.com/index.php?rid=1595515&cid=s_37614_60_f&fid=37614&url=http%3A%2F%2Fwww.babonline.org%2Fbab%2Fimps%2Frefer.htm%3FMSID%3DBA20070171 In this study, we used quantitative PCR of 16S rRNA and reductive dehalogenase genes to examine species changes and the population of Dehalococcoides species in ground water in which the dechlorination of trichloroethene to ethene was enhanced by delivery of hydrogen releasing compounds. The results have shown that at least two different Dehalococcoides species cooperate in the dechlorination of TCE to ethene. Initially, the amount of strains equipped with trichloroethene reductive dehalogenase increased about 105 fold. This was followed by a decrease to the original level, according to the exhaustion of trichloroethene. Subsequently, another strain appeared, which had a vinyl chloride reductive dehalogenase gene similar to bvcA of Dehalococcoides sp. BAV1, and is likely responsible for th... Biotechnology and Applied Biochemistry journals http://www.medworm.com/rss/comments.php?id=1595515 Thu, 04 Oct 2007 04:00:00 +0100 1595515