Department of Life Sciences and Systems Biology, University of Torino, Via Accademia Albertina 13, 10123, Torino, Italy.
Aromatase catalyses the biosynthesis of estrogens from androgens. Due to the physiological importance of this conversion of lipophilic substrates, the interaction with the lipid bilayer for this cytochrome P450 is crucial for its dynamics that must allow an easy access to substrates and inhibitors. Here, aromatase-anastrozole interaction is studied combining computational methods to identify possible access/egress routes with the protein inserted in the membrane and experimental tools aimed at the investigation of the effect of the inhibitor on the protein conformation. Read More
An electrochemical biosensor that used aptamer as a biological element was constructed to detect endotoxin. Biolayer interferometry was used to obtain the affinity constant of an aptamer for Lipopolysaccharide, which had a equilibrium dissociation constant of 22.9 nM. Read More
Key Laboratory of Science and Technology of Eco-Textile, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, 214122, China.
Silk sericin has excellent features of anti-oxidant ability and good cytocompatibility, however, high water solubility and poor mechanical properties have restricted its application in biomedical fields. In this study, aimed at improving the mechanical properties of a regenerated silk sericin, the primary hydroxy groups in silk sericin were enzymatically oxidized by using laccase and 2,2',6,6'-tetramethylpiperidine-N-oxyl (TEMPO), and the generated reactive groups then reacted further with the amino groups in the sericin chains. The efficacy of the enzymatic crosslinking was evaluated by means of determination of amino groups, SDS polyacrylamide gel electrophoresis, Fourier transform infrared (FTIR) spectroscopy, and size-exclusion chromatography. Read More
A decrease in the specific activity of an enzyme is commonly observed when the enzyme is inappropriately handled or is stored over extended period. Here, we reported a functional transition of a FMN-bound diaphorase (FMN-DI) that happened during the long-term storage process. It was found that FMN-DI did not simply lose its NADH dehydrogenase activity after a long-time storage, but obtained a new enzyme activity of NADH oxidase. Read More
Research Programme on Biomedical Informatics (GRIB), Department of Experimental and Health Sciences of Pompeu Fabra University (UPF)-Hospital del Mar Medical Research Institute (IMIM), 08003 Barcelona, Spain.
The serotonin 5-hydroxytryptamine 2A (5-HT2A ) receptor is a G-protein-coupled-receptor (GPCR) relevant for the treatment of CNS disorders. In this regard, neuronal membrane composition in the brain plays a crucial role in the modulation of the receptor functioning. Since cholesterol is an essential component of neuronal membranes, we have studied its effect on the 5-HT2A receptor dynamics through all-atom MD simulations. Read More
Department of Plant Biology, Southern Illinois University, Carbondale, IL, 62901, USA.
CYP725A4 is a P450 enzyme from Taxus cuspidata that catalyzes the formation of taxadiene-5α-ol (T5α-ol) from taxadiene in paclitaxel biosynthesis. Past attempts expressing CYP725A4 in heterologous hosts reported the formation of 5(12)-oxa-3(11)-cyclotaxane (OCT) and/or 5(11)-oxa-3(11)-cyclotaxane (iso-OCT) instead of, or in addition to, T5α-ol. Here we report that T5α-ol is produced as a minor product by Escherichia coli expressing both taxadiene synthase (TS) and CYP725A4. Read More
L-phenylalanine is an important amino acid that is widely used in the production of food flavors and pharmaceuticals. Generally, L-phenylalanine production by engineered Escherichia coli requires a high rate of oxygen supply. However, the co-expression of Vitreoscilla hemoglobin gene (vgb), driven bya tac promoter, with the genes encoding 3-deoxy-D-arabinoheptulosonate-7-phosphate synthetase (aroF) and feedback-resistant chorismate mutase/prephenate dehydratase (pheA(fbr) ), led to increased productivity and decreased demand for aeration by E. Read More
Biotechnol Appl Biochem 2017 Aug 30. Epub 2017 Aug 30.
Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran, P.O. Box: 14115-154.
Advances in nanobiotechnology and targeting strategy could improve the delivery of therapeutic molecules into cancer cells, leading to improved treatment efficiency with minimal side effects on normal cells. To design an efficient nanocarrier, consideration of parameters that facilitate direct drug delivery into the target cells is important. We studied the effect of single wall carbon nanotubes size on their cell internalization level via the folate receptor-mediated pathway through folic acid targeting. Read More
Using anti-EGFR (epidermal growth factor receptor) nanobody is a good choice for diagnoses and therapeutics for high EGFR expression diseases. In the present study, the percentage composition of anti-EGFR nanobody attained 25% of the total cell protein expressed in Escherichia coli BL21 (DE3). However, almost all nanobodies were expressed as inclusion bodies. Read More
Interleukin-6 a pleiotropic cytokine involved in wide range biological activities. So the large scale Production of biologically active recombinant human interleukin-6 is important for its structural and functional studies. Here we report an optimized method for shake flask fermentation and simplified high yield purification procedure for the recombinant interleukin -6. Read More
Phage display has been applied successfully as a tool for the generation of monoclonal antibodies (mAbs). Naive antibody libraries are unique as they are able to overcome several limitations associated with conventional mAb generation methods like the hybridoma technology. Here, we performed an in vitro selection and generation of Fab antibodies against Brugia malayi SXP protein (BmSXP), a recombinant antigen for the detection of lymphatic filariasis. Read More
In the present study, the conversion of the extract of Jerusalem artichoke tubers for mannitol production by Lactobacillus brevis 3-A5 was investigated. When the bacterium utilized enzymatic hydrolysates of Jerusalem artichoke extract as the main substrates in batch fermentation, the significant decrease in mannitol productivity was observed when the initial concentration of reducing sugar increased. Then, a strategy of continuous fed-batch fermentation was adopted for improving mannitol production with enzymatic hydrolysates of Jerusalem artichoke extract as main substrates. Read More
The recent resolution of the crystal structure of type-1 cannabinoid receptor (CB1 ), and the discovery of novel modulators for this target open the way to the possibility of elucidating the structural requirements for CB1 binding, and thereby facilitate a rational drug design. Compounds that target the orthosteric site of CB1 in some cases have shown side effects. Allosteric modulators could potentially avoid these side effects by influencing binding and/or efficacy of orthosteric ligands. Read More
Biotechnol Appl Biochem 2017 Aug 14. Epub 2017 Aug 14.
Institute of Food Science, CNR, Avellino, Italy.
Human heparanase (HPSE) is an enzyme that degrades the extracellular matrix. It is implicated in a multiplicity of physiological and pathological processes encouraging angiogenesis and tumor metastasis. The protein is a heterodimer composed from a subunit of 8 kDa and a subunit of 50 kDa. Read More
Biotechnol Appl Biochem 2017 Aug 10. Epub 2017 Aug 10.
Dairy Chemistry Division, National Dairy Research Institute, Karnal, Haryana, India.
Aflatoxin M1 (AFM1) is present in milk of lactating animals fed on aflatoxin B1 contaminated feeds. Aptamers are new emerging ligand molecules and can be employed in assay protocols. Shorter aptamers have several advantages. Read More
Optimizing alginate gel beads is necessary to support the survival, proliferation, and function of entrapped hepatocytes. In this study, gelling bath was modified by decreasing calcium ion concentration and increasing sodium ion concentration. Alginate gel beads (using 36% G sodium alginate) prepared in the modified gelling bath had more homogeneous structure and better mass transfer properties compared with the traditional gelling bath that contains only calcium ions. Read More
Lipoxygenases (LOXs) are nonheme iron-containing enzymes catalyzing the dioxygenation of polyunsaturated fatty acids. LOX catalytic activity depends on the presence of iron in the active site and the iron removal is also able to affect the membrane binding properties of the enzyme. Leukotrienes biosynthesis is initiated by the action of 5-LOX at the level of nuclear membrane and the mechanism of enzyme-membrane interaction is thought to involve structural flexibility and conformational changes at the level of the protein tertiary structure. Read More
Metformin is an AMP-activated kinase (AMPK) activator that plays a role in glucose energy metabolism and cell protection. It is widely used to treat several diseases, including type 2 diabetes, cardiovascular diseases, cancer, and metabolic diseases. In this study, we investigated whether AMPK activation upon treatment with metformin may promote neurite outgrowth during the progression of neuronal differentiation in human bone marrow-mesenchymal stem cells (hBM-MSCs). Read More
Triterpene saponins are main active constituents of Panax notoginseng. Metabolites profiling of 12 triterpene saponins was analyzed by high-performance liquid chromatography-mass spectrometry in leaf, petiole, and root extracts of P. notoginseng. Read More
Biotechnol Appl Biochem 2017 Aug 2. Epub 2017 Aug 2.
Institut de Biologie Intégrative de la Cellule, UMR 9198, Université Paris-Sud, 91405 ORSAY Cedex, France.
Small-angle X-ray Scattering (SAXS) is a relatively simple experimental technique that provides information on the global conformation of macromolecules in solution, be they fully structured, partially, or extensively unfolded. Size Exclusion chromatography in line with a SAXS measuring cell considerably improves the mono-dispersity and ideality of solutions, the two main requirements of a "good" SAXS sample. Hydrogen/Deuterium eXchange monitored by Mass Spectrometry (HDX-MS) offers a wealth of information regarding the solvent accessibility at the local (peptide) level. Read More
Alpha-1-antitrypsin (A1AT) is a major serum protein in human with protease inhibitory activity. Because of its extensive application in medicine, recombinant DNA technology has been considered for its production. The current study is going to examine co-expression of A1AT, and soluble domain of v-SNARE in Pichia pastoris, which can prevent the secretion of A1AT after passing the secretory pathway thoroughly. Read More
Amphotericin B is an effective antifungal antibiotic. However, its production in the wild-type strain of Streptomyces nodosus is relatively low. In this study, a strain of ZJB 20130827, capable of producing amphotericin B, was isolated and identified as Streptomyces nodosus, based on its physiological and biochemical characteristics as well as its 16S rRNA gene sequence analysis. Read More
In this study, we investigated the role of CB1 palmitoylation in modulating the functional interaction with G proteins both in the absence and presence of agonist binding. Our data show that the nonpalmitoylated CB1 receptor significantly reduced its association with Gαi2 . The agonist stimulation induced a partial dissociation of Gαi2 proteins from the wild-type receptor, while on the C415A mutant the agonist binding was not able to induce a significant dissociation of Gαi2 from the receptor. Read More
The growing demand for recombinant therapeutics has driven biotechnologists to develop new production strategies. One such strategy for increasing the expression of heterologous proteins has focused on enhancing cell-specific productivity through environmental perturbations. In this work, the effects of hypothermia, hyperosmolarity, high shear stress, and sodium butyrate treatment on growth and productivity were studied using three (low, medium, and high producing) CHO cell lines that differed in their specific productivities of monoclonal antibody. Read More
As promising alternatives to fossil-derived oils, microbial lipids are important as industrial feedstocks for biofuels and oleochemicals. Our broad aim is to increase lipid content in oleaginous yeast through expression of lipid accumulation genes and use Saccharomyces cerevisiae to functionally assess genes obtained from oil-producing plants and microalgae. Lipid accumulation genes DGAT (diacylglycerol acyltransferase), PDAT (phospholipid: diacylglycerol acyltransferase), and ROD1 (phosphatidylcholine: diacylglycerol choline-phosphotransferase) were separately expressed in yeast and lipid production measured by fluorescence, solvent extraction, thin layer chromatography, and gas chromatography (GC) of fatty acid methyl esters. Read More
Optimization of cellulose enzymatic hydrolysis is crucial for cost-effective bioethanol production from lignocellulosic biomass. Enzyme immobilization in solid support allows enzyme recycling for reuse, lowering hydrolysis costs. Graphene is a nanomaterial isolated in 2004, which possesses exceptional properties for biomolecule immobilization. Read More
To improve the thermostability of (R)-selective amine transaminase from Aspergillus terreus (AT-ATA), we used computer software Disulfide by Design and Modelling of Disulfide Bonds in Proteins to identify mutation sites where the disulfide bonds were most likely to form. We obtained three stabilized mutants (N25C-A28C, R131C-D134C, M150C-M280C) from seven candidates by site-directed mutagenesis. Compared to the wild type, the best two mutants N25C-A28C and M150C-M280C showed improved thermal stability with a 3. Read More
7,8-Dihydroxyflavone (7,8-DHF) has been conjugated with glucose moiety to produce glucoside derivatives. Three analogues of 7,8-DHF (7-O-β-d-glucosyl-8-hydroxyflavone, 7-hydroxy-8-O-β-d-glucosyl flavone, and 7,8-di-O-β-d-glucosylflavone) have been successfully produced from in vitro reaction using glycosyltransferase of Bacillus licheniformis. Production of these 7,8-DHF derivatives were shifted to cheaper and easier approach in this study by using engineered Escherichia coli BL21 (DE3) ΔpgiΔzwfΔushA cells in which the flow of glucose-6-phospahte toward glycolysis and pentose phosphate pathway and hydrolysis of UDP-α-d-glucose were blocked while directing the carbon flux toward UDP-α-d-glucose by overexpressing UDP-α-d-glucose pathway genes. Read More
2-Arachidonoylglycerol (2-AG) is an important endogenous signaling lipid that activates the cannabinoid receptors (CB1 R and CB2 R), thereby regulating a diverse range of physiological processes including anxiety, appetite, inflammation, memory, pain sensation, and nociception. Diacylglycerol lipases (DAGLs) are the principle enzymes responsible for 2-AG biosynthesis. Recently, the (patho)physiological functions of DAGLs have been explored by both genetic methods and chemical tools. Read More
In this study, extracellular lipase was produced by Serratia marcescens wild type and three mutant strains. The maximum lipase activity (80 U/mL) was obtained with the SMRG4 mutant strain using soybean oil. Using a 2(2) factorial design, the lipase production increased 1. Read More
Thermophilic Bacillus coagulans JI12 was used to ferment hemicellulose hydrolysate obtained by acid hydrolysis of oil palm empty fruit bunch at 50 °C and pH 6, producing 105.4 g/L of l-lactic acid with a productivity of 9.3 g/L/H by fed-batch fermentation under unsterilized conditions. Read More
It has previously been shown that exogenous application of p-coumaric acid (CA), a precursor of phenolic compounds, improved stilbene production in cell cultures of Vitis amurensis. This study examines the effect of cinnamic (Cin) and caffeic (Caf) acids, which are also phenolic precursors, on stilbene biosynthesis in the cell cultures. Five stilbenes, t-resveratrol diglucoside, t-piceid (t-resveratrol glucoside), t-resveratrol, t-ε-viniferin, and t-δ-viniferin, were found in the treated and untreated cells. Read More
The aim of this study was to investigate the optimal conditions for the immobilization and stabilization of DyP1B dye decolorizing peroxidases type B (DyP1B) from Pseudomonas fluorescens Pf-5 immobilized in Ca-alginate ferromagnetic beads. The immobilized DyP1B was used in the degradation of the Reactive Blue 5 (RB5) synthetic dye. The enzyme was successfully entrapped in a Ca-alginate matrix and showed an encapsulation efficiency of 94%. Read More
DNAzyme and aptamer conjugations have already been used for sensitive and accurate detection of several molecules. In this study, we tested the relationship between conjugation orientation of DNAzyme and aflatoxin B1 aptamer and their subsequent peroxidase activity. Circular dichroism (CD) spectroscopy and biochemical analysis were used here to differentiate between these two conjugation patterns. Read More
Current advances in medicine have revolutionized the field of regenerative medicine dramatically with newly evolved therapies for repair or replacement of degenerating or injured tissues. Stem cells (SCs) can be harvested from different sources for clinical therapeutics, which include fetal tissues, umbilical cord blood, embryos, and adult tissues. SCs can be isolated and differentiated into desired lineages for tissue regeneration and cell replacement therapy. Read More
Fibroin, the major proteinaceous component of the silk fiber produced by larvae of the domesticated silk moth (Bombyx mori), has been widely investigated as a biomaterial for potential applications in tissue engineering and regenerative medicine. Following sol-gel transition, silk fibroin solutions can generate hydrogels that present certain advantages when employed as biomaterials, especially if they are cross-linked. The subject of this study was the self-cross-linking of silk fibroin through a process induced by the enzyme horseradish peroxidase (HRP) in the presence of hydrogen peroxide, a method only recently proposed and scarcely reported. Read More
A zinc oxide (ZnO) nanowires/macroporous silicon dioxide composite was used as support to immobilize horseradish peroxidase (HRP) simply by in situ cross-linking method. As cross-linker was adsorbed on the surface of ZnO nanowires, the cross-linked HRP was quite different from the traditional cross-linking enzyme aggregates on both structure and catalytic performance. Among three epoxy compounds, diethylene glycol diglycidyl ether (DDE) was the best cross-linker, with which the loading amount of HRP with pI of 5. Read More
Biotechnol Appl Biochem 2017 Feb 21. Epub 2017 Feb 21.
The Research Center of Life Omics and Health and Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, Anhui Normal University, Wuhu, Anhui, People's Republic of China.
Isocitrate dehydrogenase (IDH) is a key enzyme at the critical junction between the tricarboxylic acid cycle and the glyoxylate cycle. Most bacteria have only one IDH, while a few contain two IDH isozymes. The coexistence of two different type IDHs in one organism was little known. Read More
Production of major effective metabolites, tanshinones and lithospermic acid B (LAB), was dramatically enhanced by exogenous jasmonate (JA) treatment in Salvia miltiorrhiza. However, the molecular mechanism of such metabolic activation in S. miltiorrhiza has not been elucidated yet. Read More
Rabies is a fatal disease that can be prevented by vaccination. Different approaches were investigated to develop novel human rabies vaccines with improved features compared to the current available vaccines, among them is the use of heterologous gene expression technology. Here, we describe the expression of the surface rabies virus glycoprotein (RABV-G), which is the major antigen responsible for the induction of protective immunity, in Pichia pastoris. Read More
Virion infectivity factor (Vif) is a 23 kDa protein that protects HIV-1 from deamination of its proviral DNA by APOBEC3G. The active form of Vif is a multimer that interacts simultaneously with CBF-beta, the elongin B and C subunits, Cullin 5, and APOBEC3G to form a ubiquitin ligase complex targeting the latter for degradation. Vif clearly represents an attractive target for developing novel antiviral drugs for the therapy of HIV/AIDS, and this goal requires a source of well folded, readily available protein. Read More
Proteus hauseri ZMd44, a biodecolorizing bacterium, has been known to produce electricity and multicopper oxidase (Mco-laccase) under copper induction. However, optimization and regulation of production have not been explored. This study is the first attempt to evaluate several parameters on biomass and Mco-laccase production of P. Read More
In this study, the binding of a glycosylated serine protease (EuP-82) with human fibrinogen was investigated by isothermal titration calorimetry (ITC). ITC analysis indicated that the binding of EuP-82 to fibrinogen in the conditions with or without the activator (Ca(2+) ) was an exothermic reaction (dominant negative enthalpy), which tended to be driven by hydrogen bonding and van der Waals interactions. In contrast, the binding of fibrinogen-EuP-82 in the condition with the inhibitor (Zn(2+) ) was an unfavorable endothermic reaction. Read More
Low-intensity pulsed ultrasound (LIPUS) is a noninvasive technique that has been shown to affect cell proliferation, migration, and differentiation and promote the regeneration of damaged peripheral nerve. Our previous studies had proved that LIPUS can significantly promote the neural differentiation of induced pluripotent stem cell-derived neural crest stem cells (iPSCs-NCSCs) and enhance the repair of rat-transected sciatic nerve. To further explore the underlying mechanisms of LIPUS treatment of iPSCs-NCSCs, this study reported the gene expression profiling analysis of iPSCs-NCSCs before and after LIPUS treatment using the RNA-sequencing (RNA-Seq) method. Read More
Alpha-momorcharin (α-MMC), a type I ribosome-inactivating protein, has attracted a great deal of attention because of its antitumor activity. However, the cytotoxicity of α-MMC is limited due to insufficient cellular internalization in cancer cells. To enhance the cytotoxicity of α-MMC, a heparin-binding domain derived from heparin-binding epidermal growth factor (named heparin-binding peptide [HBP]) was used as a cell-penetrating peptide and fused to the C-terminus of α-MMC. Read More
A simple and high sensitive cholesterol amperometric biosensor, which is based on in situ electropolymerization of multi-walled carbon nanotube-polyaniline (MWCNT-PANI) nanocomposite and electrodeposition of platinum nanoparticle (nano-Pt) films onto the glassy carbon electrode surface for cholesterol oxidase immobilization, was constructed in this study. The preparation process of the modified electrode was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy, and chronoamperometry. Because of the synergistic electrocatalytic activity between MWCNT-PANI nanocomposites and nano-Pt, the cholesterol biosensor exhibited an excellent performance with a linear range of 2. Read More
A novel sol-gel-based biosensor exploiting the optical absorption properties of sol-gel immobilized laccase has been constructed to increase enzyme specificity toward different phenolic substrates. Laccase from Trametes versicolor has been immobilized in optically transparent sol-gel matrices. Using Fourier transform infrared spectroscopy and data analysis based on a wavelet algorithm, a successful enzyme immobilization has been determined. Read More
Phytosterols have been demonstrated to be precursors of polycyclic aromatic hydrocarbons (PAHs) formed during biomass pyrolysis. Here, a novel Paenibacillus sp. was evaluated for its ability to degrade phytosterols in tobacco waste extract (TWE). Read More