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B A Dmitriev

Publications and source records attributed to B A Dmitriev.

At least 55 records · Page 3Linked to original sources

Somatic antigens of Pseudomonas aeruginosa. The structure of the O-specific polysaccharide chains of lipopolysaccharides of P. aeruginosa serogroup O4 (Lányi) and related serotype O6 (Habs) and immunotype 1 (Fisher).

Acidic O-specific polysaccharides were isolated on mild acidic degradation of lipopolysaccharides of Pseudomonas aeruginosa serotypes O4a,b, O4a,c, O4a,d (Lányi classification) and serologically related to them serotype O6 (Habs classification) and immunotype 1 (Fisher classification). The polysaccharides had identical monosaccharide composition and were built up of L-rhamnose, 2-acetamido-2,6-dideoxy-D-glucose,2-formamido-2-deoxy-D-galacturonic acid and 2-acetamido-2-deoxy-D-galactouronamide residues. The latter two derivatives of D-galactosaminuronic acid were found in nature for the first time. All the polysaccharides, but Lányi serotype O4a,c, contained O-acetyl groups. The polysaccharides were readily de-O-acetylated with aqueous triethylamine and de-N-formylated with dilute hydrochloric acid. De-N-formylated polysaccharide of serotype O4a,c was selectively cleaved with nitrous acid upon 2-amino-2-deoxygalacturonic acid residues to form a tetrasaccharide with a 2,5-anhydrotaluronic acid residue on the reducing end. The tetrasaccharide represented a modified repeating unit of the polysaccharide. Solvolysis of all intact polysaccharides with hydrogen fluoride selectively split the glycosidic linkages of 6-deoxy sugars to give the same trisaccharide, including both derivatives of galactosaminuronic acid and having 2-acetamido-2,6-dideoxyglucose on the reducing end. Structural investigation of the oligosaccharides obtained together with methylation analysis and 13C nuclear magnetic resonance data revealed the following structures of the O-specific polysaccharides: (Formula: see text) An independent confirmation of the structures of the repeating units was obtained as the result of full interpretation of the 13C nuclear magnetic resonance spectra of the intact and modified polymers. Spectral data analysis revealed a number of regularities in the effects of glycosidation connecting their values with the anomeric and absolute configuration of pyranose residues. The data on the structures of the O-specific polysaccharides indicated that each of the five P. aeruginosa strains under study should be considered as an individual O-serotype within one O-serogroup.

Antigens, Bacterial↗

Somatic antigens of Pseudomonas aeruginosa. The structure of the O-specific polysaccharide chains of P. aeruginosa O11 (Lányi) lipopolysaccharides.

Lipopolysaccharides were isolated from the phenol layer on aqueous phenol extraction of cells of Pseudomonas aeruginosa O11 (Lányi classification), strains 170021 and 170040. On mild acid degradation of the lipopolysaccharides, with the subsequent gel-filtration on Sephadex G-50, neutral O-specific polysaccharides made up of 6-deoxysugars alone were obtained. Two 2-acetamido-2,6-dideoxy-L-galactose (LFucNAc), 2-acetamido-2,6-dideoxy-D-glucose (DQuiNAc) and L-rhamnose (LRha) residues were found to be the components of the strain 170021 polysaccharide repeating units; those of strain 170040 contained the same monosaccharides, but, instead of 2-acetamido-2,6-dideoxy-D-glucose residue, that of 2-acetamido-2,6-dideoxy-D-galactose (DFucNAc) was present. On the basis of the 13C nuclear magnetic resonance data, methylation analysis and three successive Smith degradations the following structures were determined for the polysaccharide repeating units: strain 170021----2) LRha(alpha 1----3)LFucNAc(alpha 1----3)LFucNAc(alpha 1----3)DQuiNAc(beta 1----; strain 170040,----2)LRha(alpha 1----3)LFucNAc-(alpha 1----3)LFucNAc(alpha 1----3)DFucNAc(beta 1----; differing from one another by configuration of C-4 of 2-acetamido-2,6-dideoxy-D-hexopyranose only.

Antigens, Bacterial↗

[Somatic antigens of the Brucella genus. The structure of the O-specific polysaccharide chain of Brucella melitensis lipopolysaccharide].

The phenol-phase soluble antigenic lipopolysaccharide was isolated from Brucella melitensis, strain 565, by the routine phenol/water procedure followed by chromatography on Sepharose 4B. After mild acid hydrolysis and chromatography on Sephadex G-50, the lipopolysaccharide yielded a linear O-specific polysaccharide built up from 1,2-linked 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units. The structure of the polysaccharide was deduced mainly from the nuclear magnetic resonance and methylation analyses. The phenol-soluble lipopolysaccharide, isolated from commercial vaccine strain B. abortus 19-BA, on mild hydrolysis afforded material, 13C and 1H-NMR spectra of which were identical to those of the O-specific polysaccharide from B. melitensis 565.

Antigens, Bacterial↗

[Antigenic bacterial polysaccharides. 14. Structure of the O-specific polysaccharide chain of a lipopolysaccharide from Pseudomonas aeruginosa (Lányi)].

The lipopolysaccharide from Pseudomonas aeruginosa O12 (Lányi classification) gave on mild acid hydrolysis an O-specific polysaccharide built of D-ribose and N-acetyl-D-galactosamine. The disaccharide structure----4)-alpha-GalNAcp-(1----2)-beta-Ribf-(1----for the repeating unit of the polysaccharide was established by nondestructive way involving full interpretation of its 1H- and 13C-NMR-spectra, using homonuclear and selective heteronuclear 13C[1H] double resonances.

Antigens, Bacterial↗

A new type of carbohydrate-containing synthetic antigen: synthesis of carbohydrate-containing polyacrylamide copolymers having the specificity of O:3 and O:4 factors of Salmonella.

The synthesis of a new type of synthetic antigen that contains no protein is described. Two linear polyacrylamide copolymers with carbohydrate branches were obtained via radical copolymerisation of the allyl glycosides of the oligosaccharide determinants O-beta-D-mannopyranosyl-(1----4)-O-alpha-L-rhamnopyranosyl-(1----3 )-beta-D- galactopyranose and O-3,6-dideoxy-alpha-D-xylo-hexopyranosyl-(1----3)-alpha-D-mannopyranose with acrylamide. These copolymers, which contained 30% of carbohydrate and had molecular masses exceeding 100 kilodaltons, had the group specificity E and B of Salmonella.

Antigens, Bacterial↗

Structural studies of the O-specific side chain of the lipopolysaccharide from Escherichia coli O:7.

The structure of the O-specific side-chain of the lipopolysaccharide from Escherichia coli O:7 has been investigated, using n.m.r. spectroscopy, methylation analysis, partial hydrolysis, and Smith degradation as the principal methods. It is concluded that the polysaccharide is constructed of repeating pentasaccharide units having the structure (formula; see text) where D-QuipNAc stands for 4-acetamido-4,6-dideoxy-D-glucopyranose. The 13C-n.m.r. spectrum of the polysaccharide has been interpreted completely.

Carbohydrate Conformation↗

The structure and immunochemical specificity of 0-antigens of 03 serogroup Pseudomonas aeruginosa.

Using the method of phenol-aqueous extraction, lipopolysaccharides (LPS) were isolated from 5 strains (subgroups) belonging to 03 serogroup of P. aeruginosa (4). Specific polysaccharides were isolated from the LPS by means of acid hydrolysis. It has been established that the polysaccharides determining O-antigenic specificity have a uniform structure. They consist of repeated trisaccharide links comprising: 2,3(1-acetyl-2-methyl-2-imidazolino-5,4)-2,3-dideoxy-D-mannuronic acid (Im) 2,3-diacetamido-2,3-dideoxy uronic acid with -D-manno-(M) or -L-gulo-(G) configuration and 2-acetamido-2-deoxy-D-fucose (F) with alpha or beta configuration of the glycosidic bond. The structure of 0/3a/3d, 3f polysaccharide has not been definitely cleared up. Serological analysis using passive haemagglutination reaction (PHAR) testifies to the presence of antigenic cross activity of all the five LPS. Antigenic specificity of LPS of the individual subgroups was revealed in passive haemagglutination inhibition reaction (PHAIR). Partial cross activity was clearly demonstrated in immunoprecipitation experiments in the five subgroups. Serological properties of the LPS of P. aeruginosa 03 subgroup essentially correlate with the structure of their polysaccharide chains determining O-antigenic specificity.

Antigens, Bacterial↗

[A carbohydrate-containing copolymer with the specificity of a capsular polysaccharide of type 3 Streptococcus pneumoniae].

The synthesis of allyl beta-glycoside of cellobiuronic acid by chemical modification of cellobiose was described. The carbohydrate-containing polymers with different content of determinant groups were obtained via radical copolymerization of this hapten with acrylamide. The copolymer which contained 27% carbohydrates and had molecular mass about 100-300 kilodaltons had the serological specificity of the capsular polysaccharide Streptococcus pneumoniae type 3 as shown by an enzyme linked immunosorbent assay.

Chemical Phenomena↗

Somatic antigens of Shigella: the structure of the polysaccharide chain of Shigella boydii type 2 lipopolysaccharide.

The structure of the polysaccharide chain of Shigella boydii type 2 lipopolysaccharide was established using mainly 13C-n.m.r. spectroscopy, partial hydrolysis, Smith degradation, and methylation analysis. The repeating unit of the polysaccharide was concluded to be a branched hexasaccharide, as follows: (formula in text). Acetaldehyde was detected in the hyrolysate of the lipopolysaccharide, but no evidence was obtained to indicate that acetaldehyde is located in the polysaccharide moiety.

Carbohydrate Conformation↗

Cell-wall lipopolysaccharide of Escherichia coli 0114:H2. Structure of the polysaccharide chain.

The O-specific polysaccharide of the 0114 antigen (lipopolysaccharide) of Escherichia coli 0114 and oligosaccharides obtained from it by Smith degradation and hydrogen fluoride solvolysis were analyzed, using proton and 13C nuclear magnetic resonance spectroscopy and methylation. The results indicated that the 0114 polysaccharide has the tetrasaccharide repeating unit alpha-N-acetylglucosamine(1 leads to 4) beta-3,6-dideoxy-3-(N-acetyl-L-seryl)aminoglucose(1 leads to 3) beta-ribofuranose(1 leads to 4)galactose. In the polysaccharide the repeating units are joined through beta 1 leads to 3-galactosyl linkages. This structure is compared with that of the serologically cross-reacting Shigella boydii 08 antigen and the serological similarity is discussed.

Cell Wall↗

Somatic antigens of Pseudomonas aeruginosa. The structure of O-specific polysaccharide chains of P. aeruginosa O:3(a),c and O:3a,d,e lipopolysaccharides.

On mild acid degradation of Pseudomonas aeruginosa O:3(a),c, O:3a,d,e and O:3(a),d,f lipopolysaccharides O-specific polysaccharides were isolated. The trisaccharide repeating units of O:3(a),c and O:3a,d,e polysaccharides contained 2-acetamido-2,6-dideoxy-D-galactose and 2,3-(1-acetyl-2-methyl-2-imidazolino-5, 4)-2,3-dideoxy-D-mannuronic acid, which were identified previously as the constituents of P. aeruginosa O:3a,b and O:3a,d O-specific polysaccharides, as well as 2,3-diacetamido-2, 3-dideoxyl-L-guluronic acid, which has never before been found in nature. The last monosaccharide was identified without being isolated in the free state, by means of 13C nuclear magnetic resonance spectroscopy. The structures of O:3(a),c and O:3a,d,e polysaccharides were established by selective hydrogen fluoride solvolysis followed by modification of the trisaccharides obtained and analysis of the 13C nuclear magnetic resonance spectra at each modification stage. The polysaccharides possessed similar structures of repeating units differing from each other in the anomeric configuration of the N-acetylfucosamine residue only: leads to 4)DManImU-(beta 1 leads to 4) LGul(NAc)2U(alpha 1 leads to 3)DFucNAc(beta 1-and leads to 4)DManImU(beta 1 leads to 4)LGul(NAc)2U(alpha 1 leads to 3)DFucNAc(alpha 1-, where DManImU = 2,3-(1-acetyl-2-methyl-2-imidazolino-5,4)-2,3-dideoxy-D-mannuronic acid, LGul(NAc)2U = 2,3-diacetamido-2,3-dideoxy-L-guluronic acid, DFucNAc = 2-acetamido-2,6-dideoxy-D-galactose. The same components were detected in the O:3(a),d,f polysaccharide but not in the same stoichiometric ratio; this polysaccharide possessed no regular structure. The immunochemical study of lipopolysaccharides of all five P. aeruginosa O:3 serotypes showed a definite interrelation between their serological properties and structures of the corresponding O-specific polysaccharides.

Antigens, Bacterial↗

[Preventive activity of an artificial antigen possessing the serological specificity of Salmonella O-factor 3].

3-0 [4-0 (beta-D-mannopyranosyl)-alpha-L-rhamnopyranosyl]-beta-allyl-D- galactopyranoside with acrylamide, a new synthetic antigen possessing the narrow specificity of Salmonella O-factor 3, was found to protect mice, when introduced into the animals by multiple intraperitoneal injections, from the action of the live culture of Salmonella anatum and the toxic doses of its endotoxin.

Acrylamides↗