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B A Dmitriev

Publications and source records attributed to B A Dmitriev.

88 records · Page 5Linked to original sources
PubMed1976

New sugars from antigenic lipopolysaccharides of bacteria: identification and synthesis of 3-O-[(R)-1-carboxyethyl]-L-rhamnose, an acidic component of Shigella dysenteriae type 5 lipopolysaccharide.

A new acidic sugar, 3-O-[(R)-1-carboxyethyl]-L-rhamnose (1), has been identified as a constituent of the O-antigenic lipopolysaccharide of Sh. dysenteriae type 5. The structure of 1 has been established by physico-chemical methods and by synthesis. Alkylation of methyl 2,5-di-O-benzyl-alpha-L-rhamnofuranoside (6) with (S)- or (R)-2-chloropropionic acids, followed by removal of the protecting groups, afforded 3-O-[(R)-1-carboxyethyl]-L-rhamnose (9) and 3-O-[(S)-1-carboxyethyl]-L-rhamnose (10), respectively. The properties of 1 coincide with those of 9.

Antigens, Bacterial↗
PubMed1975

Somatic antigen of Shigella dysenteriae type 3. Structural features of specific polysaccharide chain.

On mild acid hydrolysis of lipolysaccharide from Shigella dysenteriae type 3 the O-specific polysaccharide (hapten) was obtained which appeared to be acidic branched hexosaminoglycan. The repeating unit of this polysaccharide represents a pentasaccharide composed of two D-galactose residues, N-acetyl-D-galactosamine, D-glucose and unidentified acidic component. On the basis of methylation analysis, periodate oxidation, partial acid hydrolysis and chromic anhydride oxidation it is concluded that the structure of the chemical repeating unit of polysaccharide is (see article) where Glcp is glucopyranose, Galp is galactopyranose, Galf is galactofuranose, GalNAcp is 2-acetamido-2-deoxygalactopyranose and where the configuration of galactofuranoside glycosidic linkage and the structure of the acidic monosaccharide A are not known.

Aluminum↗
PubMed1975

Selective cleavage of glycosidic linkages: studies with the O-specific polysaccharide from Shigella dysenteriae type 3.

Treatment of the O-specific polysaccharide from Shigella dysenteriae Type 3 with hydrazine in the presence of hydrazine sulphate resulted in quantitative N-deacetylation with the formation of a modified polysaccharide containing free amino groups. Oxidation of the modified polysaccharide with periodate did not destroy the 2-amino-2-deoxygalactose residues, thus indicating that they were substituted at position 3. Acid hydrolysis of the modified polysaccharide afforded 3-O-(2-amino-2-deoxy-beta-D-galactopyranosyl)-D-galactose, which was identified as the N-acetyl derivative. Deamination of the modified polysaccharide with nitrous acid cleaved the 2-amino-2-deoxy-D-galactopyranosyl linkages to give a pentasaccharide as the major product, which appeared to be the modified chemical repeating unit of the O-specific polysaccharide.

Acetylation↗
PubMed1975

Selective cleavage of glycosidic linkages: studies with the polysaccharide component of Shigella dysenteriae type 6 lipopolysaccharide.

The polysaccharide component obtained from the lipopolysaccharide of Shigella dysenteriae type 6 was subjected to milk hydrolysis with acid, and the products were fractionated on Sephadex G-50. An acidic hexosaminoglycan and a core oligosaccharide fraction were obtained, the former containing D-glucose, D-galactose, 2-acetamido-2-deoxy-D-galactose (in the ratios 1:1:1), and an unidentified acidic component (X). The hexosaminoglycan was N-deacetylated and then hydrolysed and deaminated to give 3-O-(2-amino-2-deoxy-beta-D-galactopyranosyl)-D-galactose (1), identified as the N-acetyl derivative (2), and 2,5-anhydro-3-O-(6-O-alpha-D-galactopyranosyl-alpha-D-glucopyranosyl)talitol (3). On the basis of the structure of 2 and the methylation-analysis data for the polysaccharide and 3, together with that for the determination of linkage configurations by chromic anhydride oxidation, the hexosaminoglycan is considered to have the repeating structure (see article).

Glycosides↗
PubMed1975

Synthesis of O-beta-D-mannopyranosyl-1 leads to 4)-O-alpha-L-rhamnopyranosyl-(1 leads to 3)-D-galactopyranose, the trisaccharide repeating-unit of the o-specific polysaccharide from Salmonella anatum.

Glycosylation of 1,2:5,6-di-O-idopropylidene-alpha-D-galactofuranose with 2,3-di-O-acetyl-4-O-(2,3,4,6-tetra-O-acetyl-beta-D-mannopyranosyl)-alpha-L-rhamnopyranosyl bromide, followed by removal of the protecting groups, gave O-beta-D-mannopyranosyl-(1 leads to 4)-O-alpha-L-rhamnopyranosyl-(1 leads to 3)-D-galactose, which is the trisaccharide repeating-unit of the O-specific polysaccharide chain of the lipopolysaccharide from Salmonella anatum. The formation of the beta-D-mannopyranosyl linkage was achieved by a glucose-mannose conversion via stereoselective reduction of the corresponding oxo-disaccharide.

Antigens, Bacterial↗
PubMedDate not supplied

[The immunological activity of Neisseria meningitidis lipo-oligosaccharide incorporated into liposomes].

Immune response to lipooligosaccharide (LOS), isolated from group B N. meningitidis cell wall, was studied after its incorporation into liposomes. The adjuvant effect produced by liposomal LOS, more pronounced in comparison with that produced by native LOS, was observed after the injection of the preparation by different routes (intravenous, intraperitoneal and subcutaneous injections), but the highest level of response was achieved after the intravenous and intraperitoneal injections of the preparation. Experiments aimed at the study of the dynamics of plaque-forming cells and the level of antibodies after intraperitoneal immunization of CBA mice with LOS revealed that immune response to liposomal LOS was more intense and prolonged than that to the free antigen. Liposomal LOS induced genetically nonrestricted and T-independent immune response. This fact was confirmed in experiments on mice having different haplotypes, such as CBA (k), C57BL/6 (b), BALB/c (d) and in nude mice with congenital thymic aplasia. In addition, liposomal LOS induced mainly the accumulation of IgM and IgG and did not produce the effect of immunological memory.

Animals↗