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1.
Infect Immun ; 51(3): 919-26, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2868993

RESUMO

Escherichia coli strains with defined receptor specificity were used as probes to analyze the individual variation in host cell receptors with respect to blood groups. The adhesins were initially characterized as mannose sensitive (MS), mannose resistant (MR), or nonagglutinating (-). The receptor specificity of the strains with MR adhesins was defined by agglutination of synthetic Gal alpha 1----4Gal beta covalently linked via a spacer arm, (CH2)2S(CH2)2CO approximately H-bovine serum albumin (BSA) to BSA-latex beads as specific for the globoseries glycolipid receptors (MR:GS). Strains with MR adhesins not reacting with Gal alpha 1----4Gal beta-BSA-latex were designated MR:nonGS. The attachment and hemagglutination of the MR:GS strains was strictly dependent on Gal alpha 1----4Gal beta-containing receptors, as shown by the absence of binding to cells from individuals of blood group P lacking these structures. Previous reports showed differences in the composition of globoseries glycolipids between erythrocytes from individuals of P1 and P2. No significant difference was found, However, in the mean adhesion to P1 and P2 epithelial cells or in the agglutination titer for P1 and P2 erythrocytes. The MR:GS receptors were equally distributed on squamous and transitional epithelial cells. In contrast, the distribution of MR:nonGS receptors was skewed. Attachment occurred mostly to squamous epithelial cells. The attachment of strains with MR:nonGS adhesins was independent of the P blood group of the cell donor. The binding ability of MR:GS and MR:nonGS adhesins appeared independent and additive. The attachment was not influenced by the ABH blood group. However, increased binding to epithelial cells from nonsecretors occurred regardless of the P blood group, suggesting a shielding of receptors by products controlled by the secretor genes. These results illustrate how individual variation in cell surface components with and without receptor activity determine the interaction of a ligand with a known receptor.


Assuntos
Proteínas de Bactérias/metabolismo , Antígenos de Grupos Sanguíneos , Escherichia coli/patogenicidade , Glicolipídeos/metabolismo , Hemaglutininas/metabolismo , Infecções Urinárias/microbiologia , Adesinas de Escherichia coli , Adesividade , Sequência de Carboidratos , Epitélio/microbiologia , Humanos
2.
Carbohydr Res ; 129: 63-71, 1984 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-6467248

RESUMO

The title compounds were prepared via the acetylated 2-bromoethyl beta-glycoside (5) of alpha-D-Gal-(1----4)-beta-D-Gal-(1----4)-beta-D-GlcNAc by displacement of bromide ion with methyl 3-mercaptopropionate, octadecanethiol, and hydrogen, respectively. Silver triflate-promoted glycosylation of 2-bromoethyl 3,6-di-O-benzyl-2-deoxy-2-phthalimido-beta-D-glucopyranoside with 2,3,6-tri-O-acetyl-4-O-(2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl) -alpha-D-galactopyranosyl bromide gave 5. The spacer-arm glycoside derived from methyl 3-mercaptopropionate was coupled to bovine serum albumin and key-hole limpet haemocyanin to give neoglycoproteins.


Assuntos
Antígenos de Grupos Sanguíneos , Oligossacarídeos/síntese química , Sistema do Grupo Sanguíneo P , Configuração de Carboidratos , Sequência de Carboidratos , Glicoproteínas/síntese química , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética
3.
Carbohydr Res ; 127(1): 15-25, 1984 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-6713439

RESUMO

The title compounds were prepared via the acetylated 2-bromoethyl glycoside 11 of alpha-D-Gal-(1----4)-beta-D-Gal-(1----4)-beta-D-Glc by displacement of bromide ion with methyl 3- mercaptopropionate , octadecanethiol , and hydrogen, respectively. Silver triflate -promoted glycosylation of 2-bromoethyl 2,3,6-tri-O-benzyl-beta-D-glucopyranoside with 2,3,6-tri-O-acetyl-4-O-(2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl) -alpha -D-galactopyranosyl bromide gave 11. A tetradeuterated analogue of 11 was prepared by essentially the same route. The spacer-arm glycoside formed from methyl 3- mercaptopropionate was coupled to bovine serum albumin and keyhole limpet haemocyanin.


Assuntos
Antígenos de Grupos Sanguíneos , Globosídeos/síntese química , Glicoproteínas/síntese química , Glicoesfingolipídeos/síntese química , Triexosilceramidas , Humanos
4.
Carbohydr Res ; 127(1): 27-33, 1984 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-6713440

RESUMO

Enzymic hydrolysis of pullulan, followed by acetylation and chromatography, gave acetylated alpha-D-Glcp-(1----6)-alpha-D-Glcp-(1----4)-alpha-D-Glcp-(1----4)-D-Glcp which, with 2-bromoethanol and boron trifluoride etherate in dichloromethane, gave the 2-bromoethyl glycoside. The reactions of the glycoside with methyl 3- mercaptopropionate , methyl 11- mercaptoundecanoate , and octadecanethiol are described, and also its hydrogenolysis to give an ethyl glycoside. The mercaptopropionate -derived, spacer-arm glycoside has been coupled to bovine serum albumin and keyhole limpet haemocyanin.


Assuntos
Oligossacarídeos/síntese química , Glucanos , Humanos , Oligossacarídeos/imunologia , Oligossacarídeos/urina
5.
Carbohydr Res ; 125(2): 237-45, 1984 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-6704994

RESUMO

The applicability of 2-bromoethyl glycosides in carbohydrate synthesis is demonstrated by the synthesis of glycosides of alpha-L-Fuc-(1----2)-D-Gal and beta-D-Gal-(1----4)-D-GlcNAc. The bromoethyl aglycon was transformed into the methoxycarbonylethylthioethyl spacer, which allowed coupling of the sugars to proteins (BSA and KLH).


Assuntos
Glicoproteínas/síntese química , Acetilglucosamina , Fenômenos Químicos , Química , Fucose , Galactose
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