The Experts below are selected from a list of 156 Experts worldwide ranked by ideXlab platform
H. N. Kirkman - One of the best experts on this subject based on the ideXlab platform.
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Measurements of Uridine Diphosphate Glucose and Uridine Diphosphate galactose--an appraisal.
European journal of pediatrics, 1995Co-Authors: H. N. KirkmanAbstract:The recent disproof of a major deficiency of Uridine Diphosphate galactose in galactosemia should not lead investigators to assume either that enzymatic methods are unreliable for Uridine sugar assays or that a defect in galactosylation in galactosemia has been excluded.
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Erythrocytic Uridine Diphosphate galactose in galactosaemia
Journal of Inherited Metabolic Disease, 1992Co-Authors: H. N. KirkmanAbstract:An earlier claim of a deficiency of Uridine Diphosphate galactose in erythrocytes of galactosaemia patients was not confirmed. Enzymic techniques similar to those of the earlier investigators were used to determine not only the concentration of Uridine Diphosphate galactose but also the ratio of this concentration to the sum of the Uridine sugar Diphosphates (Uridine Diphosphate galactose and Uridine Diphosphate Glucose). The values in erythrocytes of galactosaemic subjects were similar to those of non-galactosaemic children on a galactose-restricted diet and to those of normal adults. These results cast doubt on the claim of a major deficiency of Uridine Diphosphate galactose in galactosaemia and on the need for treating galactosaemic children with Uridine.
Atsushi Nakagawa - One of the best experts on this subject based on the ideXlab platform.
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purification and characterization of recombinant sugarcane sucrose phosphate synthase expressed in e coli and insect sf9 cells an importance of the n terminal domain for an allosteric regulatory property
Journal of Biochemistry, 2016Co-Authors: Widhi Dyah Sawitri, Hirotaka Narita, Etsuko Ishizakaikeda, Bambang Sugiharto, Toshiharu Hase, Atsushi NakagawaAbstract:Sucrose phosphate synthase (SPS) catalyses the transfer of glycosyl group of Uridine Diphosphate Glucose to fructose-6-phosphate to form sucrose-6-phosphate. Plant SPS plays a key role in photosynthetic carbon metabolisms, which activity is modulated by an allosteric activator Glucose-6-phosphate (G6P). We produced recombinant sugarcane SPS using Escherichia coli and Sf9 insect cells to investigate its structure-function relationship. When expressed in E. coli, two forms of SPS with different sizes appeared; the larger was comparable in size with the authentic plant enzyme and the shorter was trimmed the N-terminal 20 kDa region off. In the insect cells, only enzyme with the authentic size was produced. We purified the trimmed SPS and the full size enzyme from insect cells and found their enzymatic properties differed significantly; the full size enzyme was activated allosterically by G6P, while the trimmed one showed a high activity even without G6P. We further introduced a series of N-terminal truncations up to 171 residue and found G6P-independent activity was enhanced by the truncation. These combined results indicated that the N-terminal region of sugarcane SPS is crucial for the allosteric regulation by G6P and may function like a suppressor domain for the enzyme activity.
Dean A Sherry - One of the best experts on this subject based on the ideXlab platform.
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31 p mrs of the healthy human brain at 7 t detects multiple hexose derivatives of Uridine Diphosphate Glucose
NMR in Biomedicine, 2021Co-Authors: Jimin Ren, Craig R Malloy, Dean A SherryAbstract:Nucleotide sugars are required for the synthesis of glycoproteins and glycolipids, which play crucial roles in many cellular functions such as cell communication and immune responses. Uridine Diphosphate-Glucose (UDP-Glc) was previously believed to be the only nucleotide sugar detectable in brain by 31 P-MRS. Using spectra of high SNR and high resolution acquired at 7 T, we showed that multiple nucleotide sugars are coexistent in brain and can be measured simultaneously. In addition to UDP-Glc, these also include UDP-galactose (UDP-Gal), -N-acetyl-glucosamine (UDP-GlcNAc) and -N-acetyl-galactosamine (UDP-GalNAc), collectively denoted as UDP(G). Coexistence of these UDP(G) species is evident from a quartet-like multiplet at -9.8 ppm (M-9.8 ), which is a common feature seen across a wide age range (24-64 years). Lineshape fitting of M-9.8 allows an evaluation of all four UDP(G) components, which further aids in analysis of a mixed signal at -8.2 ppm (M-8.2 ) for deconvolution of NAD+ and NADH. For a group of seven young healthy volunteers, the concentrations of UDP(G) species were 0.04 ± 0.01 mM for UDP-Gal, 0.07 ± 0.03 mM for UDP-Glc, 0.06 ± 0.02 mM for UDP-GalNAc and 0.08 ± 0.03 mM for UDP-GlcNA, in reference to ATP (2.8 mM). The combined concentration of all UDP(G) species (average 0.26 ± 0.06 mM) was similar to the pooled concentration of NAD+ and NADH (average 0.27 ± 0.06 mM, with a NAD+ /NADH ratio of 6.7 ± 2.1), but slightly lower than previously found in an older cohort (0.31 mM). The in vivo NMR analysis of UDP-sugar composition is consistent with those from tissue extracts by other modalities in the literature. Given that glycosylation is dependent on the availability of nucleotide sugars, assaying multiple nucleotide sugars may provide valuable insights into potential aberrant glycosylation, which has been implicated in certain diseases such as cancer and Alzheimer's disease.
Robert R Klein - One of the best experts on this subject based on the ideXlab platform.
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identification of the Uridine binding domain of sucrose phosphate synthase expression of a region of the protein that photoaffinity labels with 5 azidoUridine Diphosphate Glucose
Plant Physiology, 1993Co-Authors: Michael E Salvucci, Robert R KleinAbstract:The Uridine Diphosphate-Glucose (UDP-Glc) binding domain of sucrose-phosphate synthase (SPS) was identified by overexpressing part of the gene from spinach (Spinacia oleracea). Degenerate oligonucleotide primers corresponding to two tryptic peptides common to both the full-length 120-kD SPS subunit and an 82-kD form that photoaffinity labeled with 5-azidoUridine Diphosphate-Glucose (5-N3UDP-Glc) were used in a polymerase chain reaction to isolate a partial cDNA clone. Comparison of the deduced amino acid sequence of spinach SPS with the sequences of potato sucrose synthase showed that the partial cDNA included one region that was highly conserved between the proteins. Expression of the partial cDNA clone of SPS in Escherichia coli produced a 26-kD fusion protein that photoaffinity labeled with 5-N3UDP-Glc. Photoaffinity labeling of the 26-kD fusion protein was specific, indicating that this portion of the SPS protein harbors the UDP-Glc-binding domain. Isolation of a modified peptide from the photolabeled protein provided tentative identification of amino acid residues that make up the Uridine-binding domain of SPS.
Gea Guerriero - One of the best experts on this subject based on the ideXlab platform.
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sucrose synthase gene expression analysis in the fibre nettle urtica dioica l cultivar clone 13
Industrial Crops and Products, 2018Co-Authors: Aurelie Backes, Marc Behr, Edoardo Gatti, Sylvain Legay, Stefano Predieri, Jeanfrancois Hausman, Michael K Deyholos, Giampiero Cai, Gea GuerrieroAbstract:Abstract The use and valorisation of fibre crops are sustainable solutions to reduce the world’s dependence on petroleum-derived products and fossil energy. Fibre crops have a relatively short growth cycle and provide high amounts of biomass used in different industrial sectors. Among fibre crops there is stinging nettle (Urtica dioica L.), a perennial herbaceous plant growing in temperate regions. Nettle phloem fibres (a.k.a. bast fibres) have a high cellulose content (ca. 80%) and low amount of lignin (ca. 4%); additionally, they are silky and have a high tensile strength. The gelatinous cell walls of bast fibres are primarily composed of cellulose. The biosynthesis of cellulose is dependent on the provision of Uridine Diphosphate Glucose, which, besides being formed from Glucose-1-phosphate through Uridine Diphosphate Glucose pyrophosphorylase, can also be produced via the reaction catalysed by sucrose synthase (SUS). A regulation of SUS gene expression accompanying the developmental stages of the bast fibres is therefore likely to exist along the stem of nettle plants. The objectives of this study were: 1) to identify the SUS genes in nettle and 2) to analyse their differential expression in tissues of stem internodes sampled at different heights (i.e. top, middle and bottom). The gene expression analysis is accompanied by optical and confocal microscopy observations concerning cellulose and lignin distribution. The results here presented identify 6 SUS genes in nettle belonging to the three Angiosperm groups previously reported (groups I–III). Their gene expression analysis shows a differential regulation in the stem tissues sampled at different heights, which reflects the increase in cell wall thickness of bast fibres along the stem of nettle. In particular, 3 expression patterns of genes either more expressed in young/old stem regions or peaking at the middle internode are identified with the heat map hierarchical clustering. This is the first study on the expression of SUS genes in a nettle fibre variety and on the immunohistochemical analysis of U. dioica internodes sampled at different stem heights. This work will serve as a basis for future molecular studies on a neglected, yet potential multi-purpose plant.
