Search results for "Maltose"
showing 10 items of 41 documents
Expression of Active Streptolysin O in Escherichia coli as a Maltose-Binding-Protein-Streptolysin-O Fusion Protein. The N-Terminal 70 Amino Acids are…
1996
Streptolysin 0 (SLO) is the prototype of a family of cytolysins that consists of proteins which bind to cholesterol and form very large transmembrane pores. Structure/function studies on the pore-forming cytolysin SLO have been complicated by the proteolytic inactivation of a substantial portion of recombinant SLO (rSLO) expressed in Escherichia coli. To overcome this problem, translational fusions between the E. coli maltose-binding protein (MBP) gene and SLO were constructed, using the vectors pMAL-p2 and pMAL-c2. MBP-SLO fusion proteins were degraded if secreted into the E. coli periplasm, but intact, soluble MBP-SLO fusion proteins were produced at high levels in the cytoplasm. Active S…
Molecular events associated with glucose repression of invertase in Saccharomyces cerevisiae.
1986
When S. cerevisiae growing in the presence of glucose (repressive condition) was shifted to higher temperatures, invertase was secreted. This secretion required protein synthesis, but was independent of RNA formation (Mormeneo & Sentandreu 1982). In addition accumulation of invertasespecific messenger RNA occurred in the absence of protein synthesis but was expressed only after synthesis of protein. Invertase mRNA was continuously synthesized under repressive conditions and the levels of this mRNA were regulated by the presence of glucose. The hexose regulated the concentration of this mRNA at the level of transcription and/or by sensitization of this messenger RNA. The expression of the in…
Isolation of carcinoembryonic antigen N-terminal domains (N-A1) from soluble aggregates
2011
Abstract Carcinoembryonic antigen (CEA) was identified as a prominent tumor-associated antigen in human colorectal cancer and it is still intensively investigated. However, its physiological role remains unclear. The CEA molecule is composed of seven highly hydrophobic, immunoglobulin-like domains, six of which contain a single disulphide bridge. The production of recombinant protein containing Ig-like domains in bacterial expression systems often results in partial degradation or insolubility due to aggregation hampering the analysis of their native structure and function. Here, we present a new method of expression and purification of CEA N-terminal domains (N-A1) fused to MBP in Escheric…
How hexoses and inhibitors influence the malate transport system in Zygosaccharomyces bailii
1988
When grown in fructose or glucose the cells of Zygosaccharomyces bailii were physiologically different. Only the glucose grown cells (glucose cells) possessed an additional transport system for glucose and malate. Experiments with transport mutants had lead to the assumption that malate and glucose were transported by one carrier, but further experiments proved the existence of two separate carrier systems. Glucose was taken up by carriers with high and low affinity. Malate was only transported by an uptake system and it was not liberated by starved malate-loaded cells, probably due to the low affinity of the intracellular anion to the carrier. The uptake of malate was inhibited by fructose…
Role of Solvent on Protein-Matrix Coupling in MbCO Embedded in Water-Saccharide Systems: A Fourier Transform Infrared Spectroscopy Study
2006
AbstractEmbedding protein in sugar systems of low water content enables one to investigate the protein dynamic-structure function in matrixes whose rigidity is modulated by varying the content of residual water. Accordingly, studying the dynamics and structure thermal evolution of a protein in sugar systems of different hydration constitutes a tool for disentangling solvent rigidity from temperature effects. Furthermore, studies performed using different sugars may give information on how the detailed composition of the surrounding solvent affects the internal protein dynamics and structural evolution. In this work, we compare Fourier transform infrared spectroscopy measurements (300–20K) o…
Comparative Analysis of Quality Criteria for the Control of Liquefaction at the Obtaining of Starch-Based Hydrolysates
2012
Starch hydrolysates production converts starch to different kinds of products using enzymes in two steps, liquefaction and saccharification. This study investigated three types of analysis methods for the assessing and characterization of the liquefaction process: a rheological method (to measure yield stress), a chemical method (for the determination of Dextrose Equivalent DE) and a chromatographic method (HPLC to obtain the Degrees of Polymerization DPs). Potato starch with 13.5% dry substance was liquefied with the enzyme Liquozyme Supra for two hours in optimal conditions of pH and temperature. A comparative analysis between the methods to describe the liquefaction process was realise…
Sugar profiles of Spanish unifloral honeys
1997
The levels of various sugars (fructose, glucose, sucrose, maltose, maltulose, kojibiose, isomaltose, raffinose, erlose and melezitose) as well as the glucose/fructose and glucose/water ratios were determined in different Spanish unifloral honey types (rosemary, orange blossom, lavender, sunflower, eucalyptus, heather, honeydew). Sugars were determined by gas chromatography of the trimethylsilyloxime derivatives. There were significant differences among the honey types in relation to sugar composition. Fructose, glucose, sucrose, maltose and the glucose/water ratio were selected by discriminant analysis as the better parameters for the correct classification of the honey samples into their p…
Classification of Spanish Unifloral Honeys by Discriminant Analysis of Electrical Conductivity, Color, Water Content, Sugars, and pH
2001
To ascertain the most discriminant variables for seven types of Spanish commercial unifloral honeys, stepwise discriminant analysis was performed. Fifteen parameters [pH; water content; electrical conductivity; x, y, and L, chromatic coordinates from the CIE-1931 (xyL) color space; fructose; glucose; sucrose; maltose; isomaltose; maltulose; kojibiose; and the fructose/glucose and glucose/water ratios] were considered. The studied honey types were rosemary, citrus, lavender, sunflower, eucalyptus, heather, and forest. The most discriminant variables, as selected by the multivariate program, were electrical conductivity, color (x, y, L), water content, fructose, and sucrose. All sunflower, eu…
Noninvasive Imaging Estimation of Myocardial Iron Repletion Following Administration of Intravenous Iron : The Myocardial- Trial
2020
Background Intravenous ferric carboxymaltose ( FCM ) improves symptoms, functional capacity, and quality of life in heart failure and iron deficiency. The mechanisms underlying these effects are not fully understood. The aim of this study was to examine changes in myocardial iron content after FCM administration in patients with heart failure and iron deficiency using cardiac magnetic resonance. Methods and Results Fifty‐three stable heart failure and iron deficiency patients were randomly assigned 1:1 to receive intravenous FCM or placebo in a multicenter, double‐blind study. T2* and T1 mapping cardiac magnetic resonance sequences, noninvasive surrogates of intramyocardial iron, were eval…
Changes in myocardial iron content following administration of intravenous iron (Myocardial‐IRON): Study design
2018
Treatment with intravenous ferric carboxymaltose (FCM) has been shown to improve symptoms, functional capacity, and quality of life in patients with heart failure and iron deficiency. However, the underlying mechanisms for these beneficial effects remain undetermined. The aim of this study is to quantify cardiac magnetic resonance changes in myocardial iron content after administration of intravenous FCM in patients with heart failure and iron deficiency and contrast them with parameters of heart failure severity. This is a multicenter, double-blind, randomized study. Fifty patients with stable symptomatic heart failure, left ventricular ejection fraction <50%, and iron deficiency will be r…