PubMed Health⌕ Search

Biomedical subjects

B Fournet

Publications and source records attributed to B Fournet.

At least 109 records · Page 6Linked to original sources

Structural studies on 2-acetamido-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine and 2-acetamido-6-O-(alpha-L-fucopyranosyl)-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine by 360-MHz proton-magnetic-resonance spectroscopy.

The 360-MHz proton magnetic resonance spectra of 2-acetamido-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine (GlcNAcbeta1 leads to Asn) and 2-acetamido-6-O-(alpha-L-fucopyranosyl)-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine (Fucalpha1 leads to 6GlcNAcbeta1 leads to Asn) in deuterium oxide were completely interpreted. The chemical shifts and coupling constants were refined by simulation of the spectra. By means of an adapted Karplus equation the pyranose ring conformation of the sugars was calculated. The change of the geminal coupling constant J6a,6b in the N-acetylglucosamine residue of Fucalpha1 leads to 6GlcNAcbeta1 leads to Asn with respect to GlcNAcbeta1 leads to Asn is proposed to be characteristic for the (1 leads to 6) glycosidic linkage.

Acetylglucosamine↗

[Chromatographic fractionation and studies on microheterogenity of cow lactotransferrin prepared by an original procedure].

Authors describe an original procedure to prepare pure lactotransferrin from cow milk. Physicochemical properties of this lactotransferrin have been studied and compared with results from others. New data are presented: presence of fucose and N-acetylgalactosamine; C-terminal amino-acid identified with threonine. On the other hand, 4 fractions have been obtained by "DEAE-Sephadex" chromatography, study of which demonstrates that the microheterogeneity of the lactotransferrin depends on the carbohydrate moiety and especially on the N-acetylneuraminic acid content which varies from 0 to 2 residues.

Amino Acid Sequence↗

[Isolation and structure of an external glycoprotein of the cell wall of Torulopsis candida].

The treatment with ethylenediamine of Torulopsis candida yeast cell walls has permitted to isolate a mannoprotein. It has been possible to collect this glycoprotein in a pure state after separation of the different hydrosoluble products by gel filtrations and paper electrophoresis. This compound contains 62 per cent of mannose, 3 per cent of N-acetylglucosamine and 31 per cent of amino acids. The mannose units are attached by 1 leads to 2 linkage, short oligosaccharides are bound to serine of the peptide chain by O-glycosidic linkages while polysaccharides are attached to asparagine of this peptide chain by a N glycosidic linkages probably through the intermediate of chitobiose.

Amino Acids↗

[Structure of the carbohydrate groups of IgG1 immunoglobulins of cow colostrum].

Hydrolysis by chymotrypsin of bovine immunoglobulins (IgG1, type) isolated from colostral whey yields glycopeptides, structural studies of which lead to the following results. 1. IgG1 colostral immunoglobulins possess two glycan moieties which are linked to the peptidic chain by an N-(beta-aspartyl)-N-acetylglucosaminylamine bound. 2. The peptidic sequence is Asn (Glycan)-Ser-Thr-Tyr. 3. Application of partial acidic hydrolysis, periodic oxidation, hydrazinolysis-nitrous deamination, methylation and use of specific glycosidases lead to the determination of the following structure of the glycan moieties: (see article). These structures are related to the general glycan structure so-called of "N-acetyllactosamine type" because they possess the pentasaccharidic core common to numerous glycoproteins Man alpha (1 leads to 3) [Man alpha (1 leads to 6)] Man beta (1 leads to 4) GlcNAc beta (1 leads to 4) GlcNAc beta (leads to) Asn on which are conjugated two N-acetyllactosamine residues. They present a microheterogeneity which is due to the varying number of additional N-acetylneuraminic acid and fucose residues.

Amino Acids↗

Structure of the three major sialyl-oligosaccharides excreted in the urine of five patients with three distinct inborn diseases: "I cell disease" and two new types of mucolipidosis.

The urine of five patients with three distinct diseases ("I Cell disease" and two new types of mucolipidosis) contains sialic acid-rich oligosaccharides in a high amount: 50- to 500-fold the normal. The structure of the major components are as follows: alphaAcNeu(2 leads to 6)betaGal(1 leads to 4)betaGlcNac(1 leads to 2)alphaMan(1 leads to 3)betaMan(1 leads to 4)GlcNac,[alphaAcNeu(2 leads to 6)]betaGal(1 leads to 4)betaGlcNAc(1 leads to 2)alphaMan(1 leads to 3)[betaGal(1 leads to 4)betaGlcNac(1 leads to 2)alphaMan(1 leads to 6)]betaMan(1 leads to 4)GlcNAc and alphaAcNeu(2 leads to 6)betaGal(1 leads to 4)betaGlcNAc(1 leads to 2)alphaMan(1 leads to 3)[alphaAcNeu(2 leads to 6)betaGal(1 leads to 4)betaGlcNAc(1 leads to 2)alphaMan(1 leads to 6)]betaMan(1 leads to 4)GlcNAc. These results suggest that a deficit in alpha-neuraminidase is associated to these three different disorders and that an endo-beta-D-N-acetylglucosaminidase is able to release sialyoligosaccharides by splitting the sialylglycans of glycoproteins.

Adult↗

[Studies on the cell wall of yeast of the genus Rhodotorula. X. Isolation and purification of cell-wall glycoproteins from Rhodotorula rubra (author's transl)].

Following ethylene diamine treatment of the cell wall of Rhodotorula rubra, a water soluble fraction has been isolated. This fraction can be resolved into three glycoproteins and one protein. The major part is a glycoprotein, purified to homogeneity which has a molecular weight of 64 000. The glyco-part of this protein contains mannose, glucose and one residue of glucosamine. After pronase treatment, the presence of an ""Asparaginyl-N-acetylglucosamine" linkage is established by the existence of one aspartic acid residue and one glucosamine residue. After permethylation, the initial data give some evidence that the branching points in the molecule were the carbon atoms 3 and (or) 6 of the mannose moiety and that some glucose moieties are bound to the non-reducing terminal end.

Acetylglucosamine↗

[The structure of three major oligosaccharides in the urine of patients with mucolipidosis type II and with two new types of metabolic disease].

The urine of five patients with three distinct diseases ("I Cell disease" and two new types of mucolipidosis) contains sialic acid-rich oligosaccharides in a high amount: 50 to 500 fold the normal. The structure of the major components are as follows alpha-NANA-(2 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man-(1 leads to 3)-beta-Man-(1 leads to 4)-GlcNAc, [alpha-NANA-(2 leads to 6) beta-Gal-(1 leads to 4)-beta-Glc-NAc-(1 leads to 2)-alpha-Man-(1 leads to 3) [beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man-(1 leads to 6)]-beta-Man-(1 leads to 4)-GlcNAc and alpha-NANA-(2 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man-(1 leads to 3)[alpha-NANA-(2 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man-(1 leads to 6)[-beta-Man-(1 leads to 4)-GlcNAC. These results suggest that a dieficit in alpha-neuraminidase is associated to these three different disorders and that an endo-beta-D-N-acetyglucosaminidase is able to release sialyloligosaccharides by splitting the sialyglycans of glycoproteins.

Adult↗

Hydrazinolysis and nitrous acid deamination of the carbohydrate moiety of alpha1-acid glycoprotein.

Hydrazinolysis followed by nitrous acid deamination of alpha1-acid glycoprotein gave acidic and neutral mono- and oligo-saccharides that contain 2,5-anhydro-D-mannose as reducing residue: alpha-D-Manp-(1 leads to 3)-[alpha-D-Manp-(1 leads to 6)]-beta-D-Manp-(1 leads to 4)-2,5-anhydro D-mannose (1), beta D-Galp-(1 leads to 4)-2,5-anhydro-D-mannose (3), 2,5-anhydro-D-mannose, and two N-acetylneuraminic acid-containing oligosaccharides having the common partial sequence: NeuNAc-(2 leads to ?)-[BETA-D-Galp-(1 leads to 4)-2,5-anhydro-D-mannose] (5). This specific cleavage of 2-amino-s-deoxy-D-glucosyl linkages released almost quantitatively a very limited number of saccharides. Reduction with sodium borotritide of the products of cleavage allowed the precise determination of the molar proportion of 1, 3, and free 2,5-anhydro-D-mannose.

Binding Sites↗

[Chemistry of urinary mannosides excreted in mannosidosis].

Mannose-rich oligosaccharides have been isolated from urines of 5 patients with mannosidosis. Their compositon and structure were determined. Three of them have been previously described by Norden et al: alpha p-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAcp; alpha-p-Manp-(1 leads to 2), alpha-d-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAc and alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) beta-d-Manp-(1 leads to 4) d-GlcNAcp, but the four others are new entities: alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp; alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp; alpha-d-Manp-(1 leads to 2), alpha-d-Man-(1 leads to 3) (alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAp and alpha-d-Manp-(1 leads to 2) alpha-d-Manp-(1 leads to 3) (alpha-d-Manp-(1 leads to 6) beta-d-Manp-(1 leads to 4) GlcNAcp. These structures are related to the glycans of "oligomannosidic type" present in numerous glycoproteins. All possess a N-acetylglucosamine residue in terminal reducing position and reinforce the hypothesis of Kobata et al. and Montreuil et al. that catabolism of glycans N-glucosidically linked to the protein moiety begins by the aciton of a beta-endo-N-acetylglucosaminidase.

Acetylglucosamine↗

[Complete structure of glycopeptides isolated from IgG immunoglobulins of cow colostrum].

Bovine immunoglobulins (IgG1 type) have been isolated from colostral whey. Hydrolysis by pronase, trypsin and (or) chymotrypsin yield several glycopeptides structural studies of which lead to the following results. 1. IgG1 colostral immunoglobulins possess two glycan moieties which are linked to the peptidic chain by an N-(beta-aspartyl)-N-acetylglucosaminylamine bound. 2. The peptidic sequence around the linkage region has been determined by classical methods and is as follows: Thr-Lys-Pro-Arg-Glu-Glu-Gln-Phe-Asn(Glycan)-Ser-Thr-Tyr-Arg. 3. The following procedures: partial acidic hydrolysis, periodic oxidation, hydrazinolysis-nitrous deamination, methylation and use of specific glycosidases allowed us to determine the structure of the glycan moieties which fit with the general following scheme: (see article) Thus they could be related to the general glycan structure so-called of "N-acetyllactosamine type" because they possess the pentasaccharidic core common to numerous glycoproteins Man alpha 1 leads to [Man alpha 1 leads to 6] Man beta 1 leads to 4 GlcNAc beta 1 leads to 4 GlcNAc beta 1 leads to Asn on which are conjugated 2 N-acetyllactosamine residues. Besides they present a microheterogeneity which is due to the varying number of additional N-acetylneuraminic acid and fucose residues. 4. These structures are compared to various immunoglobulin structures proposed by others: bovine serum IgG and human serum IgG, IgE and IgA.

Acetylglucosamine↗

[Structure and immunochemical properties of the urinary oligosaccharides excreted during induced galactosuria].

Induced galactosuria is characterized by the excretion in urine of large amounts of new oligosaccharides, the structure of which are in connection with blood-group phenotypes ABH, Lewis and Secretor: O group : O-alpha-L fucopyranosyl-(1 leads to 2)-D galactopyranose et O-alpha-L fucopyranosyl-(1 leads to 2)-O-beta-D galactopyranosyl-(1 leads to 3)-[O-alpha-L fucopyranosyl-(1 leads to 4)]-O-beta-D 2-deoxy-2 acetamido-glucopyranosyl-(1 leads to 4)-[O-alpha-L fucopyranosyl-(1 leads to 6)]-D-galactopyranose. A group: O-alpha-D-2-deoxy-2 acetamido-galactopyranosyl-(1 leads to 3)-[O-alpha-L fucopyranosyl-(1 leads to 2)]-D galactopyranose et O-alpha-D-2-deoxy-2 acetamido-galactopyranosyl-(1 leads to 3)-[O-alpha-L fucopyranosyl-(1 leads to 2)]-O-beta-D galactopyranosyl-(1 leads to 3)-[O-alpha-L fucopyranosyl-(1 leads to 4)]-O-beta-D-2-deoxy-2 acetamido-glucopyranosyl-(1 leads to)-[O-alpha-L fucopyranosyl-(1 leads to 6)]-D galactopyranose. B group : O-alpha-D galactopyranosyl-(1 leads to 3)-[O-alpha-L fucopyranosyl-(1 leads to 2)]-D galactopyranose et O-alpha-D galactopyranosyl-(1 leads to 3)-[O-alpha-L fucopyranosyl-(1 leads to 2)]-O-beta-D galactopyranosyl-(1 leads to 3)-[O-alpha-L fucopyranosyl-(1 leads to 4)]-O-beta-D-2-deoxy-2 acetamido-glucopyranosyl-(1 leads to 4)-[O-alpha-L fucopyranosyl-(1 leads to 6)]-D-galactopyranose.

ABO Blood-Group System↗

The sugar part of kappa-caseins from cow milk and colostrum and its microheterogeneity.

Cow kappa-casein contains only three different sugars (Gal, GalNAc, NeuNAc). However detailed analyses achieved mainly by gas liquid chromatography suggested a microheterogeneity at the sugar level. After alkaline borohydride treatment, filtration on Bio-Gel P4 and paper chromatography, different carbohydrate parts were obtained. The two main compounds had the following molar compositions: GalNAc (1), Gal(1) and NeuNAc (1) and GalNAc (1), Gal(1) and NeuNAc (2). From these data and our previous sequence studies, some formulae of the polysaccharide part were proposed. One of them was closely related to the sugar sequence of a glycopeptide with MN activity which was in agreement with our observation concerning a cross antigenic reactivity between the N blood group substances and the caseinoglycopeptides. All the polysaccharide parts isolated from colostrum caseinoglycopeptide were much more complex than those obtained from the normal glycopeptide, confirming an evolution of the sugar part as a function of time after parturition.

Acetylgalactosamine↗