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Thierry Doco - One of the best experts on this subject based on the ideXlab platform.
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Recent advances in the knowledge of wine Oligosaccharides.
Food chemistry, 2020Co-Authors: Rafael Apolinar-valiente, Pascale Williams, Thierry DocoAbstract:Abstract Oligosaccharides are carbohydrates with a low polymerization degree containing between three and fifteen monosaccharide residues covalently linked through glycosidic bonds. Oligosaccharides are related to plant defense responses and possess beneficial attributes for human health. Research has focused in wine Oligosaccharides only in the last decade. In this paper, a summary of these works is provided. They include: (i) wine Oligosaccharides origins, (ii) techniques for isolating oligosaccharide fraction and determining their content, composition and structure, (iii) their dependence on the grape origin and cultivar and winemaking process, and (iv) the connection between Oligosaccharides and wine sensorial attributes. Further research is required regarding the impact of agricultural aspects and winemaking techniques on wine Oligosaccharides. The knowledge concerning their influence on sensorial and physicochemical properties of wines and on human health should also be improved. The implementation of laboratory methods will provide better understanding of these compounds and their performance within wine’s matrix.
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Complex carbohydrates of red wine: characterization of the extreme diversity of neutral Oligosaccharides by ESI-MS.
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Thierry Doco, Pascale Williams, Emmanuelle Meudec, Veronique Cheynier, Nicolas SommererAbstract:The major neutral Oligosaccharides of a Carignan red wine have been characterized for the first time. The Oligosaccharides were prepared after removal of phenolic compounds by polyamide chromatography and of polysaccharides by alcohol precipitation and then were fractionated by anion exchange and size-exclusion chromatography. In a second step, the glycosyl composition and linkages of wine Oligosaccharides were determined. Oligosaccharide fractions were analyzed by mass spectrometry (MS) with an electrospray ionization (ESI) source and an ion trap mass analyzer after separation by hydrophilic interaction liquid chromatography on a Nucleodur HILIC column (zwitterionic sulfoalkyl betaine stationary phase). Glycosyl residue composition analysis showed the predominant presence of arabinose, with galactose, rhamnose, and mannose in lower proportion. Neutral Oligosaccharides were present at a concentration of 185 mg/L in this wine. The MS spectra in the negative ion mode of the oligosaccharide fractions showed a series of oligosaccharidic structures corresponding to oligo-arabinans often linked to the basic unit α-l-Rhap-(1 → 4)-α-d-GalpA. The wine Oligosaccharides identified correspond to arabino-Oligosaccharides, rhamno-arabino-Oligosaccharides, and different rhamnogalacturonan-arabino-Oligosaccharides with DP ranging from 5 to 49, resulting from the degradation of grape cell wall pectins. Oligosaccharides have an extreme diversity, with more than 100 peaks detected in HPLC-ESI-MS spectra corresponding each to at least one oligosaccharidic structure.
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Effect of enzyme additions on the oligosaccharide composition of Monastrell red wines from four different wine-growing origins in Spain
Food Chemistry, 2014Co-Authors: R. Apolinar-valiente, Pascale Williams, Gerard Mazerolles, I. Romero-cascales, E. Gomez-plaza, J. M. Lopez-roca, J. M. Ros-garcia, Thierry DocoAbstract:The release of Oligosaccharides during winemaking depends on the grape skin cell wall degradation, which can be facilitated by the use of enzymes. Oligosaccharide quantities and composition in wine could be influenced by the "terroir" effect. Monastrell wine was elaborated from grapes from four different "terroirs" (Canada Judio, Albatana, Chaparral-Bullas and Montealegre). Monastrell wines were also treated with beta-galactosidase enzyme addition and commercial enzyme addition. The results showed significant differences in the Monastrell wine oligosaccharide fractions, according to the geographical origin of grapes. A higher quantity of Oligosaccharides was found for three out of four terroirs studied when commercial enzymes were added. The use of commercial enzyme modified the Arabinose/Galactose and the Rhamnose/Galacturonic acid ratios in Canada Judio and Albatana terroirs wines, and it modified the (Arabinose + Galactose)/Rhamnose ratio in Canada Judio, Albatana and Chaparral-Bullas terroirs wines. Therefore, the "terroir" impacts the effect of commercial enzyme treatment on wine oligosaccharide composition.
Ajit Varki - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous Fluorescent Labelling and Biotinylation of Oligosaccharides: A Versatile Approach to the Analysis of Oligosaccharide Structure and Function
A Laboratory Guide to Glycoconjugate Analysis, 1997Co-Authors: Derek Toomre, Ajit VarkiAbstract:Oligosaccharides participate in a variety of important biological functions, including interactions with specific receptors (1–4). A prerequisite to the discovery and exploration of such interactions is the comprehensive structural analysis of homogeneous oligosaccharide species. The purification of Oligosaccharides from complex mixtures requires diverse techniques, as well as sensitive and specific detection. One way to achieve sensitive detection is to attach a chromophore to the reducing sugar by reductive amination (5, 6) (see Chapters 7,11,15,18 in this volume for other examples of such techniques). Fluorescent chromophores (in contrast to light-absorbing chromophores) can often permit detection in the low picomole range for high-pressure liquid chromatography (HPLC) and polyacrylamide gel electrophoresis (PAGE) techniques, and in the femtomole range in capillary electrophoresis. Furthermore, hydrophobic or anionic properties of the chromophoric groups can be exploited to improve oligosaccharide fractionation by either electrophoresis or HPLC (5–8). Often several multidimensional chromatographic techniques, based on different physical properties, are required to adequately resolve complex mixtures. Several examples have been described of “two-dimensional mapping” with fluorescent pyridylamino (PA)-coupled Oligosaccharides (5, 9). More recently, 2-aminobenzamide has been employed as an alternate fluorescent tag which gives both nonselective and highly efficient coupling to Oligosaccharides (10).
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biotinylated diaminopyridine an approach to tagging Oligosaccharides and exploring their biology
Proceedings of the National Academy of Sciences of the United States of America, 1993Co-Authors: B E Rothenberg, Bradley K Hayes, Derek Toomre, Adriana E Manzi, Ajit VarkiAbstract:Abstract Fluorescent tagging of free Oligosaccharides by reductive amination permits sensitive detection and fractionation of these molecules. To expand the scope of this approach, we have synthesized a fluorescent reagent, 2-amino-(6-amidobiotinyl)pyridine. This reagent can tag Oligosaccharides under nondegradative conditions with high efficiency. The resulting adducts show excellent fractionation by reverse-phase HPLC with sensitive detection in the low picomole range. When combined with sequential exoglycosidase digestion, stepwise sequencing of the sugar chains is possible. The biotinyl group can also be used to recover the sugar chain from reaction mixtures. The high-affinity interaction of the biotinyl group with multivalent avidin or streptavidin can be used to create the functional equivalent of neoglycoproteins carrying multiple copies of Oligosaccharides of defined structure. These complexes allow the production of IgG antibodies directed against the oligosaccharide chain. They can also harness the power of (strept)avidin-biotin technology for the detection and isolation of oligosaccharide-specific receptors from native sources of recombinant libraries.
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biological roles of Oligosaccharides all of the theories are correct
Glycobiology, 1993Co-Authors: Ajit VarkiAbstract:Many different theories have been advanced concerning the biological roles of the oligosaccharide units of individual classes of glycoconjugates. Analysis of the evidence indicates that while all of these theories are correct, exceptions to each can also be found. The biological roles of Oligosaccharides appear to span the spectrum from those that are trivial, to those that are crucial for the development, growth, function or survival of an organism. Some general principles emerge. First, it is difficult to predict a priori the functions a given oligosaccharide on a given glycoconjugate might be mediating, or their relative importance to the organism. Second, the same oligosaccharide sequence may mediate different functions at different locations within the same organism, or at different times in its ontogeny or life cycle. Third, the more specific and crucial biological roles of Oligosaccharides are often mediated by unusual oligosaccharide sequences, unusual presentations of common terminal sequences, or by further modifications of the sugars themselves. However, such oligosaccharide sequences are also more likely to be targets for recognition by pathogenic toxins and microorganisms. As such, they are subject to more intra- and inter-species variation because of ongoing host-pathogen interactions during evolution. In the final analysis, the only common features of the varied functions of Oligosaccharides are that they either mediate 'specific recognition' events or that they provide 'modulation' of biological processes. In so doing, they generate much of the functional diversity required for the development and differentiation of complex organisms, and for their interactions with other organisms in the environment.
Tsuguo Mizuochi - One of the best experts on this subject based on the ideXlab platform.
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Structures of the asparagine-linked oligosaccharide chains of human von Willebrand factor. Occurrence of blood group A, B, and H(O) structures.
The Journal of biological chemistry, 1992Co-Authors: Taei Matsui, Koiti Titani, Tsuguo MizuochiAbstract:Abstract The asparagine-linked oligosaccharide chains of human von Willebrand factor (vWF) purified from pooled plasma were quantitatively liberated from the polypeptide moiety by hydrazinolysis. After N-acetylation, these were fractionated by paper electrophoresis and sequential chromatography on lectin-affinity columns of concanavalin A, Phaseolus vulgaris erythrophytohemagglutinin, Datura stramonium agglutinin, Ricinus communis agglutinin 120, and Ulex europaeus agglutinin I and on a Bio-Gel P-4 column. Their structures were investigated by sequential exoglycosidase digestion in conjunction with methylation analysis. The glycoprotein was shown to be unique in its great diversity of oligosaccharide structures. Another noteworthy finding which had not been reported previously was the occurrence of asparagine-linked oligosaccharide chains with blood group A, B, and H(O) structures. In the present study, this glycoprotein was shown to contain mono- (0.4% of the total Oligosaccharides), bi-(78.2%), tri- (12.3%), and tetraantennary (2.3%) complex type Oligosaccharides in addition to a series of high mannose type Oligosaccharides, Man6-9GlcNAc2 (0.8%). Biantennary complex type oligosaccharide chains were those with (8.2%) and without (70.0%) a bisecting GlcNAc residue and approximately 13.2%, 2.2%, and 0.4% of these contained blood group H(O), A, and B structures, respectively. The tri- and tetraantennary complex type chains were those with and without N-acetyllactosamine repeats, and about 13.0% of the triantennary chains without the N-acetyllactosamine repeat contained the blood group H(O) structure. Occurrence of these asparagine-linked Oligosaccharides with blood group A and B structures suggest that the repeated use of factor VIII/vWF pooled concentrate for the treatment of hemophiliacs could result in the production of antibodies against vWF with a different blood group from that of the patient, and this development may be pathogenic.
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β subunits of equine chorionic gonadotropin and lutenizing hormone with an identical amino acid sequence have different asparagine linked oligosaccharide chains
Biochemical and Biophysical Research Communications, 1991Co-Authors: Taei Matsui, George R. Bousfield, Darrell N Ward, Hiromu Sugino, Mari Miura, Koiti Titani, Tsuguo MizuochiAbstract:The glycoprotein hormones, equine chorionic gonadotropin (eCG) and lutenizing hormone (eLH), possess a beta-subunit with an identical amino acid sequence. The Asn-linked oligosaccharide chains of eCG beta and eLH beta were quantitatively liberated as tritium-labeled Oligosaccharides by hydrazinolysis followed by N-acetylation and NaB3H4-reduction. Paper electrophoresis in combination with sialidase digestion and solvolytic desulfation indicated that eCG beta contained neutral and sialylated Oligosaccharides, while eLH beta contained neutral, sialylated, sulfated, and both sialylated and sulfated Oligosaccharides. In addition, elution profiles on a Bio-Gel P-4 column of the neutralized oligosaccharide mixtures of eCG beta and eLH beta were different, indicating that the molecular masses of Oligosaccharides of the two glycoproteins are different. Therefore, this suggests that the structures of the Asn-linked oligosaccharide chains of eCG beta and eLH beta are different although they have an identical amino acid sequence.
Emma R Master - One of the best experts on this subject based on the ideXlab platform.
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altered substrate specificity of the gluco oligosaccharide oxidase from acremonium strictum
Biotechnology and Bioengineering, 2011Co-Authors: Maryam Foumani, Thu V Vuong, Emma R MasterAbstract:A gluco-oligosaccharide oxidase (GOOX) from Acremonium strictum type strain CBS 346.70 was cloned and expressed in Pichia pastoris. The recombinant protein, GOOX-VN, contained fifteen amino acid substitutions compared with the previously reported A. strictum GOOX. These two enzymes share 97% sequence identity; however, only GOOX-VN oxidized xylose, galactose, and N-acetylglucosamine. Besides monosaccharides, GOOX-VN oxidized xylo-Oligosaccharides, including xylobiose and xylotriose with similar catalytic efficiency as for cello-Oligosaccharides. Of three mutant enzymes that were created in GOOX-VN to improve substrate specificity, Y300A and Y300N doubled kcat values for monosaccharide and oligosaccharide substrates. With this novel substrate specificity, GOOX-VN and its variants are particularly valuable for oxidative modification of cello- and xylo-Oligosaccharides. Biotechnol. Bioeng. 2011;108: 2261–2269. © 2011 Wiley Periodicals, Inc.
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Altered substrate specificity of the gluco‐oligosaccharide oxidase from Acremonium strictum
Biotechnology and Bioengineering, 2011Co-Authors: Maryam Foumani, Thu V Vuong, Emma R MasterAbstract:A gluco-oligosaccharide oxidase (GOOX) from Acremonium strictum type strain CBS 346.70 was cloned and expressed in Pichia pastoris. The recombinant protein, GOOX-VN, contained fifteen amino acid substitutions compared with the previously reported A. strictum GOOX. These two enzymes share 97% sequence identity; however, only GOOX-VN oxidized xylose, galactose, and N-acetylglucosamine. Besides monosaccharides, GOOX-VN oxidized xylo-Oligosaccharides, including xylobiose and xylotriose with similar catalytic efficiency as for cello-Oligosaccharides. Of three mutant enzymes that were created in GOOX-VN to improve substrate specificity, Y300A and Y300N doubled kcat values for monosaccharide and oligosaccharide substrates. With this novel substrate specificity, GOOX-VN and its variants are particularly valuable for oxidative modification of cello- and xylo-Oligosaccharides. Biotechnol. Bioeng. 2011;108: 2261–2269. © 2011 Wiley Periodicals, Inc.
Stuart E. H. Moore - One of the best experts on this subject based on the ideXlab platform.
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Transport of free polymannose-type Oligosaccharides from the endoplasmic reticulum into the cytosol is inhibited by mannosides and requires a thapsigargin-sensitive calcium store
Glycobiology, 1998Co-Authors: Stuart E. H. MooreAbstract:The transport of free polymannose-type Oligosaccharides from the lumen of the endoplasmic reticulum into the cytosol has been recently demonstrated (Moore,S.E.H., et al., 1995, EMBO J., 14, 6034-6042), but at present little is known of the characteristics of this process. Here, it is shown that inhibition of the transport of endogenously synthesized metabolically radiolabeled free Oligosaccharides out of the endoplasmic reticulum into the cytosol of permeabilized HepG2 cells occurs when assays are conducted in the presence of mannose (IC50, 4.9 mM), or its derivatives modified at the first carbon (C1) of the sugar ring; alpha-methyl mannoside (IC50, 2.0 mM), mannoheptulose (IC50, 1.6 mM), and alpha-benzyl mannoside (IC50, 0.8 mM), whereas other monosaccharides (50 mM), differing from mannose at position; C2 (glucose), C3 (altrose), C4 (talose), C5 (l-rhamnose), and C6 (mannoheptose), have little effect. N-Acetylglucosamine does not inhibit oligosaccharide transport and, furthermore, although mannobioses and a mannotriose inhibit free oligosaccharide transport, di-N-acetylchitobiose is without effect. It is also shown that if the transport assay buffer is either depleted of calcium ions, or supplemented with the Ca2+/Mg2+ATPase inhibitor, thapsigargin, or with calcium ionophores, free oligosaccharide transport out of the endoplasmic reticulum is inhibited. These results demonstrate that the terminal nonreducing mannosyl residues of free polymannose-type Oligosaccharides and not their N-acetylglucosamine-containing reducing termini, play an important role in the interaction of the free oligosaccharide with the transport machinery, and that this transport process requires the presence of calcium sequestered in the lumen of the endoplasmic reticulum.
