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Biomedical subjects

B Fournet

Publications and source records attributed to B Fournet.

At least 91 records · Page 5Linked to original sources
PubMed1981

Localization and overall structure of a mannose-rich glycopeptide from a pathologic immunoglobulin.

The structure of a mannose-rich glycopeptide from a human pathological IgM has been investigated. It belongs to the group I (simple) glycopeptides and contains only mannose and N-acetylglucosamine residues in a molar ratio of 10:2. The structures of its oligosaccharide moiety and peptide chain have been determined: its molecular localization is specified and the relation between its biosynthesis and the oligosaccharide structure determine is discussed. Based on the alpha- and beta-mannosidase digestions and permethylation studies for the oligosaccharide moiety, and on the results obtained after sequential analysis of the peptide chain, the following structure is proposed for the mannose-rich IgM Du glycopeptide: (Formula: see text). The recovery of one molecule of this glycopeptide per molecule of heavy chain and the determination of the amino acid sequence have led us to locate this glycopeptide on asparagine 402 of the Fc portion of the heavy chain mu of IgM Du.

Amino Acid Sequence↗
PubMed1981

Metabolism of lipoproteins in rodent malaria, relationship between lipolysis, steatosis and increased biosynthesis of V.L.D.L.

The kinetic study of the seric free fatty acids, total lipids and hepatic triacyglycerides had led us to conclude that the biosynthesis of T.A.G.-rich lipoproteins increases during malaria. It seems that the parasite induces a lipolysis of adipose tissue in order to meet its own needs for fatty acids and that the excess of the latter taken by the liver involves an increased synthesis of the V.L.D.L. The cis-vaccenic acid has also been analysed during the evolution of parasitaemia; these variations by themselves cannot explain the extra parasitic hemolysis.

Adipose Tissue↗
PubMed1981

Structure determination by 360-MHz 1H-NMR spectroscopy and methylation analysis of a biantennary glycan of the N-acetyllactosaminic type isolated from rat-liver plasma membrane.

Glycopeptides obtained by exhaustive pronase digestion of delipidated rat liver plasmic membranes were purified by gel filtration on Sephadex G-25. These glycopeptides were further fractionated by affinity chromatography on a concanavalin-A--Sepharose 4B column into the following fractions: (a) glycopeptides which did not bind to the column (fraction 1); (b) glycopeptides with weak affinity for concanavalin-A--Sepharose, which could be eluted with buffer only (fraction 2); (c) glycopeptides retained on the column and which could be eluted specifically with buffer containing 0.2 M methyl alpha-glucoside (fraction 3). On the basis of the carbohydrate composition, methylation analysis and 360-MHz 1H-NMR spectroscopy, the following primary structure of a glycan in fraction 2 is proposed: (see formula in text).

Amino Acids↗
PubMed1979

The primary structure of the asialo-carbohydrate units of the first glycosylation site of human plasma alpha 1-acid glycoprotein.

The elucidation of the structures of the carbohydrate units linked to glycosylation site I of human plasma alpha 1-acid glycoprotein is described. These carbohydrate units can be grouped into compounds with bi- (class A) and triantennary (class B) structures and the triantennary structure with a fucose residue (class BF) (Fig. 1). The structural variability of the carbohydrate units of glycosylation site I and also of glycosylation sites II to V (Fournet, B., Montreuil, J., Strecker, G., Dorland, L., Haverkamp, J., Vliegenthart, J.F.G., Binette, J.P. and Schmid, K. (1978) Biochemistry 17, 5206--5214) accounts largely for the microheterogeneity of alpha 1-acid glycoprotein.

Carbohydrate Conformation↗
PubMed1979

Investigation by 360-MHz 1H-nuclear-magnetic-resonance spectroscopy and methylation analysis of the single glycan chain of chicken ovotransferrin.

The primary structure of two glycopeptides obtained by pronase digestion of chicken ovotransferrin has been investigated by 360-MHz proton nuclear magnetic resonance (NMR) spectroscopy and methylation analysis. The two glycopeptides differ in amino acid composition but contain the same carbohydrate moiety, viz: (formula: see text). Using the NMR data of some reference compounds the chemical shifts of the anomeric protons and mannose H-2 protons could be predicted with an accuracy of 0.01 ppm.

Animals↗
PubMed1979

Cow kappa-casein: structure of the carbohydrate portion.

The detailed sugar sequences of the two main carbohydrate portions of cow kappa-casein were established by enzymic and chemical methods and by mass spectrometry. The sugar sequences correspond to widespread sugar parts occurring in many glycoproteins.

Animals↗
PubMed1978

[Spatial conformation of human serotransferrin glycans].

The construction of molecular models for the human serotransferrin glycans shows that they present one compact section linked to the protein and constituted by the pentasaccharide alpha-Man-(1 leads to 3)-[alpha-Man-(1 leads to 6)]-beta-Man-(1 leads to 4)-beta-GlcNAc-(1 leads to 4)-beta-GlcNAc-(1 leads to)-Asn to which are attached two "antennae" consisting of the trisaccharide alpha-NANA-(2 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc. The trisaccharide sequence beta-Man-(1 leads to 4)-beta-GlcNAc-(1 leads to 4)-beta-GlcNAc adopts a flat and rigid conformation, stabilised by hydrogen bonds. In contrast, the sequence alpha-NANA-(1 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man takes up a helical configuration. The two "antennae" can be disposed on the pentasaccharide core to give two possible configurations, one Y-shaped and the other T-shaped. In both cases, the general conformation of the glycans is perfectly compatible with their postulated role as a recognition signal.

Chemical Phenomena↗
PubMed1978

360-MHz 1H nuclear-magnetic-resonance spectroscopy of sialyl-oligosaccharides from patients with sialidosis (mucolipidosis I and II).

360-MHz proton nuclear magnetic resonance spectra were recorded of 10 sialyl-oligosaccharides isolated from urine of sialidosis patients. Their structures are related to the complex asparagine-linked glycan chains of glycoproteins. By correlation of these spectra and comparison with spectra of reference glycopeptides and sialyl-lactose isomers it was possible to assign all signals belonging to anomeric, mannose H-2, sialic acid H-3 and N-acetyl protons. The number of the consituting monosaccharide residues of the oligomers can be obtained by integration of the above-mentioned signals. The chemical shifts of the anomeric and mannose H-2 protons give information about the type of glycan structure (mono-, bi-, triantennary) and the presence of terminal sialic acid at each of the antennas. The chemical shifts of sialic acid H-3 protons are typical for sialic acid residues in 2 leads to 3 or 2 leads to 6 linkage to galactose.

Carbohydrates↗
PubMed1978

The carbohydrates of influenza virus. II. Gas chromatographic analysis of glycopeptides derived from viral glycoproteins and mucopolysaccharides.

Two carbohydrate fractions can be obtained from egg-grown influenza virus after Pronase digestion followed by gel chromatography. One fraction contains glycopeptides (MW ca. 2000--2600) which represent the carbohydrate side chains of the viral glycoproteins. The constituent sugars of this material are fucose, galactose, glucosamine, and mannose, and their position within the side chain has been partially elucidated by methylation studies. The other fraction (MW greatest than 6000) appears to be mucopolysaccharide and is composed of fucose, galactose, glucose, galactosamine, and glucosamine.

Chromatography, Gas↗
PubMed1978

Structure of the three major fucosyl-glycoasparagines accumulating in the urine of a patient with fucosidosis.

Fifteen fucosyl-oligosaccharides and fucosyl-glycoasparagines have been isolated from the urine of a patient with fucosidosis. The structure of the three most abundant glycoasparagines are as follows: alpha-Fuc-(1 lead to 6)-beta-GlcNAc-Asn; alpha-Man-(1 leads to 6)-beta-Man-(1 leads to 4)-beta-GlcNAc-(1 lead to 4) [alpha-Fuc-(1 leads to 6)]-belta-GlcNAc-Asn; beta-Gal-(1 leads to 4) [alpha-Fuc-(1 lead to 3)] beta-GlcNAc-(1 leads to 2)-alpha-Man-(1 lead to 6)-beta-Man-(1 leads to 4)-beta-GlcNAc-(1 leads to 4) [alpha-Fuc-(1 leads to 6)] beta-GlcNAc-Asn. The structures are related to the class of fucosyl-glycoproteins (e.g.: IgG immunoglobulin, lactotransferrin and alpha 1-acid glycoprotein). The terminal sequence: beta-Gal-(1 leads to 4) [alph-Fuc-(1 leads to 3)] beta-GlcNAc-(1 leads to 2)-a-Man leads to R is novel for carbohydrate moieties in glycoproteins.

Carbohydrate Metabolism, Inborn Errors↗
PubMed1977

[Physicochemical properties of an extracellular polysaccharide isolated from culture media of Bacillus amyloliquefaciens].

A new extracellular polysaccharide has been isolated by chromatography on anion exchanger of a fraction obtained from highly viscous culture media of Bacillus amyloliquefaciens. This polysaccharide is characterised by high molecular weight (1,000,000 dalton) and intrinsic viscosity (323 ml/g). It contains 24% neutral sugar (galactose and mannose 5:1), 35% glucuronic acid and 51.5% N-acetylhexosamines (N-actylglucosamine, N-acetylgalactosamine and N-acetylbacillosamine 6:9:1).

Bacillus↗
PubMed1977

Structure of seven oligosaccharides excreted in the urine of a patient with Sandhoff's disease (GM2 gangliosidosis-variant O).

The urine of a patient with Sandhoff's disease (GM2 gangliosidosis-variant O) contains 10--12 N-acetylglucosamine-rich oligosaccharides in high amounts. The structures of seven of these have been determined: beta-GlcNAc(1--2)-alpha-Man-(1--3)-beta-man-(1--4)-GlcNAc; beta-GlcNAc-(1--4)-alpha-Man-(1--3)-beta-Man-(1--4)-GlcNAc; beta-GlcNAc-(1--2)-alpha-Man-(1--6)-beta-Man-(1--4)-GlcNAc; beta-GlcNAc-(1--4)-alpha-Man-(1--6)-beta-Man-(1--4)-GlcNAc; beta-GlcNAc-(1--2)-alpha-Man-(1--3)-[beta-GlcNAc-(1--2)-alpha-Man-(1--6)]beta-Man-(1--4)-GlcNAc; beta-GlcNAc-(1--2)-alpha-Man-(1--3)[beta-GlcNAc-(1--2)-alpha-Man-(1--6)][beta-GlcNAc-(1--4)]beta-Man-(1--4)-GlcNAc; beta-GlcNAc-(1--2)-alpha-Man(1)-(1--3)[beta-GlcNAc-(1--2)-alpha-Man(2)-(1--6)]beta-Man-(1--4)-GlcNAc, with additional beta-GlcNAc, with additional beta-GlcNAc-(1--4) on mannose (1) or (2). An unusual oligosaccharide, with a tri-branched beta-mannose, has been characterized as the major component excreted in urine.

Acetylglucosamine↗