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Diabetes & Vascular Disease Research Jan 2012Hyperglycaemia and glucose degradation products (GDPs) are closely associated with oxidative stress and inflammation in diabetic patients, a condition that leads to...
Hyperglycaemia and glucose degradation products (GDPs) are closely associated with oxidative stress and inflammation in diabetic patients, a condition that leads to endothelial dysfunction and cardiovascular problems. We evaluated the effect of citrate and gluconate on glucose- and GDP-induced endothelial inflammation by measuring changes in viability, inflammation and function in primary human umbilical vein endothelial cells (HUVECs). The extent of apoptosis/necrosis was measured by flow cytometry and visualised with confocal microscopy by staining with annexin V or propidium iodide, respectively. Protein kinase C-βII (PKC-βII) activation was evaluated with Western blotting. Incubation with glucose (30 mM) and GDP (50 µM) significantly increased PKC-βII expression, endothelial cell death and inflammation. The addition of citrate decreased hyperglycaemia-induced apoptosis (p = 0.021), necrosis (p = 0.04) and reduced PKC-βII expression (p = 0.021) down to background levels. Citrate improved endothelial function by reducing the inflammatory markers (p = 0.01) and by decreasing neutrophil diapedesis (p = 0.012). These results suggest that citrate may have therapeutic potential by reducing hyperglycaemia-induced endothelial inflammation and abolishing endothelial dysfunction.
Topics: Anti-Inflammatory Agents; Apoptosis; Blotting, Western; Cell Survival; Cells, Cultured; Citric Acid; Coculture Techniques; Enzyme Activation; Flow Cytometry; Gluconates; Glucose; Human Umbilical Vein Endothelial Cells; Humans; Hyperglycemia; Inflammation; Intercellular Adhesion Molecule-1; Microscopy, Confocal; Necrosis; Neutrophils; Protein Kinase C; Protein Kinase C beta; Pyrones; Transendothelial and Transepithelial Migration
PubMed: 22045866
DOI: 10.1177/1479164111424297 -
International Journal of Biological... Sep 2021This study aims to examine the effect of ethanol and lactic acid on the production of bacterial cellulose, and determine the optimal composition of a co-supplemented... (Comparative Study)
Comparative Study
This study aims to examine the effect of ethanol and lactic acid on the production of bacterial cellulose, and determine the optimal composition of a co-supplemented culture using response surface methodology. Both ethanol and lactic acid, when added separately or jointly, affected the yield and properties of the biomaterial. Optimization resulted in an increase of 470% in the yield, compared to the Schramm-Hestrin medium. Culture growth profiles, substrate consumption and by-products generation, were examined. The growth rate was increased for cultures supplemented with lactic acid and both lactic acid and ethanol, while the production of gluconic acid was diminished for all modified cultures. The properties of BNC, such as the structure, crystallinity, water holding capacity and tensile strength, were also determined. BNC produced in optimal conditions is more porous and characterized by wider fibers. Despite a decrease in crystallinity, by the addition of ethanol, lactic acid and both additives, the ratio of cellulose Iα was almost unchanged. The stress, strain, young modulus and toughness were improved 2.8-4.2 times, 1-1.9 times, 2.4-3.5 times and 2.5-6.8 times, respectively. The new approach to improving BNC yields and properties presented here could contribute to more economical production and wider application of this biopolymer.
Topics: Acetic Acid; Cellulose; Crystallization; Elastic Modulus; Ethanol; Gluconacetobacter xylinus; Gluconates; Glucose; Hydrogen-Ion Concentration; Lactic Acid; Tensile Strength; Water
PubMed: 34324907
DOI: 10.1016/j.ijbiomac.2021.07.147 -
PloS One 2012Excessive NaCl intake is associated with a variety of fibrosing diseases such as renal and cardiac fibrosis. This association has been attributed to increased blood...
Excessive NaCl intake is associated with a variety of fibrosing diseases such as renal and cardiac fibrosis. This association has been attributed to increased blood pressure as the result of high NaCl intake. However, studies in patients with high NaCl intake and fibrosis reveal a connection between NaCl intake and fibrosis that is independent of blood pressure. We find that increasing the extracellular concentration of NaCl to levels that may occur in human blood after high-salt intake can potentiate, in serum-free culture conditions, the differentiation of freshly-isolated human monocytes into fibroblast-like cells called fibrocytes. NaCl affects the monocytes directly during their adhesion. Potassium chloride and sodium nitrate also potentiate fibrocyte differentiation. The plasma protein Serum Amyloid P (SAP) inhibits fibrocyte differentiation. High levels of extracellular NaCl change the SAP Hill coefficient from 1.7 to 0.8, and cause a four-fold increase in the concentration of SAP needed to inhibit fibrocyte differentiation by 95%. Together, our data suggest that NaCl potentiates fibrocyte differentiation. NaCl-increased fibrocyte differentiation may thus contribute to NaCl-increased renal and cardiac fibrosis.
Topics: Cell Differentiation; Gluconates; Humans; Monocytes; Nitrates; Serum Amyloid P-Component; Sodium Chloride
PubMed: 23029177
DOI: 10.1371/journal.pone.0045674 -
Journal of Bacteriology Dec 1963Deibel, R. H. (American Meat Institute Foundation, Chicago, Ill.), Donald E. Lake, and C. F. Niven, Jr. Physiology of the enterococci as related to their taxonomy. J....
Deibel, R. H. (American Meat Institute Foundation, Chicago, Ill.), Donald E. Lake, and C. F. Niven, Jr. Physiology of the enterococci as related to their taxonomy. J. Bacteriol. 86:1275-1282. 1963-Studies on a collection of enterococci isolated from diverse sources have confirmed the existence of two distinct species, namely, Streptococcus faecalis and Streptococcus faecium. In contrast with S. faecium, S. faecalis characteristically ferments melezitose, sorbitol, glycerol (anaerobically), citrate, and gluconate; fails to ferment arabinose and melibiose; has strong reducing capacities as demonstrated by prompt reduction of litmus in milk or tetrazolium in an agar medium; initiates growth on an agar medium containing 0.04% potassium tellurite; does not require folic acid for growth; and does not produce strong greening in blood agar. S. liquefaciens and S. zymogenes differ from S. faecalis only in their proteolytic capacities and, therefore, deserve only varietal status. Some S. faecalis and S. faecium strains are proteolytic when tested on agar media. S. durans differs from S. faecium only in its inability to ferment arabinose and mannitol, and the failure of most strains to ferment sucrose. Therefore, it should be considered as a variety of S. faecium. It is recommended that the term "enterococcus" be used only when referring to S. faecalis and S. faecium, and their respective varieties.
Topics: Arabinose; Carbohydrate Metabolism; Citrates; Classification; Culture Media; Enterococcus; Enterococcus faecalis; Enterococcus faecium; Fermentation; Folic Acid; Fumarates; Gelatin; Gluconates; Glucose; Glycerol; Mannitol; Metabolism; Research; Streptococcus
PubMed: 14086101
DOI: 10.1128/jb.86.6.1275-1282.1963 -
Ultrasonics Sonochemistry Jun 2018Galactooligosaccharides (GOS), recognised prebiotic, can be industrially produced from lactose and commercial β-galactosidase (β-gal) from Kluyveromyces lactis....
Galactooligosaccharides (GOS), recognised prebiotic, can be industrially produced from lactose and commercial β-galactosidase (β-gal) from Kluyveromyces lactis. Residual lactose and glucose limit GOS applications. To handle this problem, a multienzymatic system, with β-gal and glucose oxidase (Gox), was proposed to reduce glucose content in reaction media through its oxidation to gluconic acid (GA). Besides, ultrasound (US) probe effect over the multienzymatic system to produce GOS and GA has been evaluated. A production around 40% of GOS was found in all treatments after the first hour of reaction. However, glucose consumption and GA production was significantly higher (P < 0.05) for sequential reaction assisted by US, obtaining the best production of GOS (49%) and GA (28%) after 2 h of reaction. The conformational and residual activity changes of enzymes under US conditions were also evaluated, Gox being positively affected whereas in β-gal hardly any change was found.
Topics: Galactose; Gluconates; Glucose Oxidase; Hydrolysis; Kluyveromyces; Oligosaccharides; Prebiotics; Ultrasonic Waves; beta-Galactosidase
PubMed: 29680601
DOI: 10.1016/j.ultsonch.2018.02.022 -
The NMR signature of gluconoylation: a frequent N-terminal modification of isotope-labeled proteins.Journal of Biomolecular NMR Feb 2019N-terminal gluconoylation is a moderately widespread modification in recombinant proteins expressed in Escherichia coli, in particular in proteins bearing an N-terminal...
N-terminal gluconoylation is a moderately widespread modification in recombinant proteins expressed in Escherichia coli, in particular in proteins bearing an N-terminal histidine-tag. This post-translational modification has been investigated mainly by mass spectrometry. Although its NMR signals must have been observed earlier in spectra of C/N labeled proteins, their chemical shifts were not yet reported. Here we present the complete H and C chemical shift assignment of the N-terminal gluconoyl post-translational modification, based on a selection of His-tagged protein constructs (CCL2, hnRNP A1 and Lin28) starting with Met-Gly-...-(His). In addition, we show that the modification can hydrolyze over time, resulting in a free N-terminus and gluconate. This leads to the disappearance of the gluconoyl signals and the appearance of gluconate signals during the NMR measurements. The chemical shifts presented here can now be used as a reference for the identification of gluconoylation in recombinant proteins, in particular when isotopically labeled.
Topics: Gluconates; Isotope Labeling; Nuclear Magnetic Resonance, Biomolecular; Protein Processing, Post-Translational; Recombinant Proteins
PubMed: 30737614
DOI: 10.1007/s10858-019-00228-6 -
Neurotoxicology Jan 2017Previous studies have suggested that oral zinc supplementation can help reduce the duration of the common cold; however, the use of intranasal (IN) zinc is strongly...
Previous studies have suggested that oral zinc supplementation can help reduce the duration of the common cold; however, the use of intranasal (IN) zinc is strongly associated with anosmia, or the loss of the sense of smell, in humans. Prior studies from this lab showed that upregulation of metallothioneins (MT) is a rapid and robust response to zinc gluconate (ZG). Therefore, we assessed the role of MT in the recovery of nasal epithelial damage resulting from IN zinc administration. The main studies in this investigation used a high dose of ZG (170mM) to ensure ablation of the olfactory mucosa, so that the progression of histological and functional recovery could be assessed. In vivo studies using wild-type, MT1/2 knockout mice (MT KO), and heterozygotes administered ZG by IN instillation showed profound loss of the olfactory mucosa in the nasal cavity. Recovery was monitored, and a lower percentage of the MT KO mice were able to smell 28 d after treatment; however, no significant difference was observed in the rate of cell proliferation in the basal layer of the olfactory epithelium between MT KO and wild-type mice. A lower concentration of ZG (33mM), equivalent to that found in homeopathic IN ZG preparations, also caused olfactory epithelial toxicity in mice. These studies suggest that the use of zinc in drug formulations intended for IN administration in humans must be carefully evaluated for their potential to cause olfactory functional deficits.
Topics: Administration, Intranasal; Animals; Dose-Response Relationship, Drug; Gluconates; Matrix Metalloproteinase 14; Matrix Metalloproteinase 15; Mice; Mice, Transgenic; Olfaction Disorders; Olfactory Mucosa; Proliferating Cell Nuclear Antigen; Thiazoles
PubMed: 27979773
DOI: 10.1016/j.neuro.2016.12.003 -
Metabolic Engineering Jul 2019The genus Pseudomonas comprises approximately 200 species with numerous isolates that are common inhabitants of soil, water, and vegetation and has been of particular...
The genus Pseudomonas comprises approximately 200 species with numerous isolates that are common inhabitants of soil, water, and vegetation and has been of particular interest for more than one hundred years. Here, we present a novel approach for accurate, precise and convenient C metabolic flux analysis of these and other microbes possessing periplasmic glucose oxidation and a cyclic hexose metabolism, which forms the recently discovered EDEMP cycle. This complex cyclic architecture cannot be resolved by common metabolic flux workflows, which rely on GC-MS-based labelling analysis of proteinogenic amino acids. Computational analyses revealed that this limitation can be overcome by three parallel labelling experiments on specific tracers, i.e., [1-C], [6-C] and 50% [C] glucose, with additional consideration of labelling information from glucose and glucosamine. Glucose and glucosamine display building blocks from cellular glycogen, peptidoglycan and lipopolysaccharides, reflect the pools of glucose6-phosphate and fructose6-phosphate in the heart of the EDEMP cycle and as we show, can be precisely assessed in biomass hydrolysates by GC-MS. The developed setup created 534 mass isotopomers and enabled high-resolution flux analysis of the cell factory Pseudomonas putida KT2440 and the human pathogen P. aeruginosa PAO1. The latter strain oxidized approximately 90% of its glucose into gluconate via the periplasmic route, whereas only a small fraction of substrate was phosphorylated and consumed via the cytoplasmic route. The oxidative pentose phosphate pathway was completely inactive, indicating the essentiality of the Entner-Doudoroff pathway and recycling of triose units into anabolic precursors. In addition to pseudomonads, many microbes operate a cyclic hexose metabolism, which becomes more accessible to flux analysis with this approach. In this regard, the presented approach displays a valuable extension of the available set of flux methods for these types of bacteria.
Topics: Gas Chromatography-Mass Spectrometry; Gluconates; Glucose; Metabolic Flux Analysis; Oxidation-Reduction; Pentose Phosphate Pathway; Pseudomonas aeruginosa; Pseudomonas putida
PubMed: 30831266
DOI: 10.1016/j.ymben.2019.01.008 -
Journal of Bacteriology Apr 2000We have identified a family of six hexose transporter genes (Ght1 to Ght6) in the fission yeast Schizosaccharomyces pombe. Sequence homology to Saccharomyces cerevisiae... (Comparative Study)
Comparative Study
We have identified a family of six hexose transporter genes (Ght1 to Ght6) in the fission yeast Schizosaccharomyces pombe. Sequence homology to Saccharomyces cerevisiae and mammalian hexose transporters (Hxtp and GLUTp, respectively) and secondary-structure predictions of 12 transmembrane domains for each of the Ght proteins place them into the sugar porter subfamily within the major facilitator superfamily. Interestingly, among this sugar porter family, the emerging S. pombe hexose transporter family clusters are separate from monosaccharide transporters of other yeasts (S. cerevisiae, Kluyveromyces lactis, and Candida albicans) and of humans, suggesting that these proteins form a distinct structural family of hexose transporters. Expression of the Ght1, Ght2, Ght5, and Ght6 genes in the S. cerevisiae mutant RE700A may functionally complement its D-glucose uptake-deficient phenotype. Northern blot analysis and reverse transcription-PCR showed that among all Ght's of S. pombe, Ght5 is the most prominently expressed hexose transporter. Ght1p, Ght2p, and Ght5p displayed significantly higher specificities for D-glucose than for D-fructose. Analysis of the previously described S. pombe D-glucose transport-deficient mutant YGS-5 revealed that this strain is defective in the Ght1, Ght5, and Ght6 genes. Based on an analysis of three S. pombe strains bearing single or double mutations in Ght3 and Ght4, we conclude that the Ght3p function is required for D-gluconate transport in S. pombe. The function of Ght4p remains to be clarified. Ght6p exhibited a slightly higher affinity to D-fructose than to D-glucose, and among the Ght's it is the transporter with the highest specificity for D-fructose.
Topics: Amino Acid Sequence; Biological Transport; Cloning, Molecular; Fructose; Fungal Proteins; Gene Expression; Genes, Fungal; Gluconates; Glucose; Glycerol; Maltose; Molecular Sequence Data; Monosaccharide Transport Proteins; Multigene Family; Mutation; Recombinant Proteins; Saccharomyces cerevisiae; Schizosaccharomyces; Schizosaccharomyces pombe Proteins; Sequence Analysis, DNA; Sequence Homology, Amino Acid
PubMed: 10735857
DOI: 10.1128/JB.182.8.2153-2162.2000 -
Anaesthesia Nov 1980Various preparations of calcium are recommended for use in treatment of cardiac arrest and advantages are claimed for one preparation over another because of increased...
Various preparations of calcium are recommended for use in treatment of cardiac arrest and advantages are claimed for one preparation over another because of increased availability of the calcium to the heart. Ionised calcium levels in human blood have been assayed following the addition of calcium increments by use of the calcium electrode. The results showed no difference between calcium chloride and calcium gluconate.
Topics: Calcium; Calcium Chloride; Calcium Gluconate; Electrodes; Gluconates; Heart Arrest; Humans; Osmolar Concentration
PubMed: 7446909
DOI: 10.1111/j.1365-2044.1980.tb05043.x