Biomedical subjects

A S Shashkov

Publications and source records attributed to A S Shashkov.

At least 91 records · Page 5Linked to original sources

PubMed1999

Structure and serological specificity of a new acidic O-specific polysaccharide of Proteus vulgaris O45.

The following structure of the O-specific polysaccharide (OPS) of Proteus vulgaris O45 lipopolysaccharide (LPS) was established using 1H- and 13C-NMR spectroscopy, including two-dimensional NOESY and H-detected 1H, 13C heteronuclear multiple-quantum coherence ( HMQC) experiments: [structure: see text text] Immunochemical studies, using rabbit polyclonal anti-P. vulgaris O45 serum and LPS, OPS and Smith-degraded OPS of P. vulgaris O45, showed the importance of beta-D-GlcA in manifesting the serological specificity of the O-antigen studied.

Carbohydrate Sequence↗

PubMed1999

Structure of the O-specific polysaccharide of a serologically separate strain Proteus penneri 2 from a new proposed serogroup O66.

O-specific polysaccharide chain of Proteus penneri strain 2 lipopolysaccharide was studied by full and partial acid hydrolysis, Smith degradation, methylation analysis, and NMR spectroscopy, including two-dimensional rotating-frame NOE spectroscopy (ROESY) and 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments. Together with D-glucose and 2-acetamido-2-deoxy-D-glucose, the polysaccharide was found to contain two rarely occurring sugars, 6-deoxy-L-talose (L-6dTal) and 2,3-diacetamido-2,3,6-trideoxy-L-mannose (L-RhaNAc3NAc), and the following structure of a non-stoichiometrically O-acetylated tetrasaccharide repeating unit was established: [equation: see text] The O-specific polysaccharide studied has a unique composition and structure and, accordingly, P. penneri 2 is serologically separate among Proteus strains. Therefore, we propose for P. penneri 2 a new Proteus O-serogroup O66 where this strain is at present the single representative.

Carbohydrate Conformation↗

PubMed1999

Structural and serological studies on the O-antigen of Proteus mirabilis O14, a new polysaccharide containing 2-[(R)-1-carboxyethylamino]ethyl phosphate.

An O-specific polysaccharide was obtained by mild acid degradation of Proteus mirabilis O14 lipopolysaccharide (LPS) and found to contain D-galactose, 2-acetamido-2-deoxy-D-glalactose, phosphate, N-(2-hydroxyethyl)-D-alanine (D-AlaEtn), and O-acetyl groups. Studies of the initial and O-deacetylated polysaccharides using one- and two-dimensional 1H- and 13C-NMR spectroscopy, including COSY, TOCSY, NOESY, H-detected 1H,13C heteronuclear multiple-quantum coherence, and heteronuclear multiple-bond correlation experiments, demonstrated the following structure of the repeating unit: [equation: see text] This is the second bacterial polysaccharide reported to contain alpha-D-Galp6PAlaEtn, whereas the first one was the O-antigen of P. mirabilis EU313 taken erroneously as strain PrK 6/57 from the O3 serogroup [Vinogradov, E. V., Kaca, W., Shashkov, A.S., Krajewska-Pietrasik, D., Rozalski, A., Knirel, Y.A. & Kochetkov, N.K. (1990) Eur. J. Biochem., 188, 645-651]. Anti-(P. mirabilis O14) serum cross-reacted with LPS of P. mirabilis EU313 and vice versa in passive hemolysis and ELISA. Absorption of both O-antisera with the heterologous LPS decreased markedly but did not abolish the reaction with the homologous LPS. These and chemical data indicated that both strains have similar but not identical O-antigens. Therefore, we propose that P. mirabilis EU313 should belong to a new subgroup of the O14 serogroup.

Carbohydrate Conformation↗

PubMed1999

Cell wall teichoic acids of Actinomadura viridis VKM Ac-1315T.

The cell walls of Actinomadura viridis contain poly(glycosylglycerol phosphate) chains of complex structure. On the basis of NMR spectroscopy of the polymer and glycosides thereof the following structural units were found: beta-D-Galp3Me-(1-->4)[beta-D-Glcp-(1-->6)]-beta-D-Galp-(1-->1)-++ +snGro (G1); beta-D-Galp-(1-->4)-beta-D-Galp-(1-->1)-snGro (G2); beta-D-Galp3Me-(1-->4)-beta-D-Galp-(1-->1)-snGro (G2a); beta-D-Galp-(1-->1)-snGro (G3); beta-D-Galp-(1-->1)[beta-D-Galp-(1-->2)]-snGro (G4); beta-D-Glcp-(1-->2)-snGro (G5). Glycosides G1, G2 and G3 were the predominant components of the teichoic acid: they formed the polymer chain via phosphodiester bonds involving C-3 of the glycerol residue and C-3 of the galactosyl residue which in turn glycosylates C-1 of the glycerol residue. Whether the different glycosides make up the one chain or whether there are several poly(glycosylglycerol phosphate) chains in the cell wall remains to be determined. It was suggested that the minor component G5 is located at the nonterminal end of the chains. Compound G4 which contains disubstituted glycerol residues (unusual for the teichoic acid) was also found as a minor component; this may be the glycoside of a new type of teichoic acid, or a glycoside on the terminal end of the above mentioned chains. In addition, small amounts of 1,3-poly(glycerol phosphate) chains were found in the cell wall.

Actinomycetales↗

PubMed1999

Structure of a neutral O-specific polysaccharide of the bacterium Providencia alcalifaciens O5.

A neutral polysaccharide containing D-galactose, 2-acetamido-2-deoxy-D-glucose, and 3-acetamido-3,6-dideoxy-D-glucose (Qui3NAc) in the ratios 2:1:1 was obtained by mild acid degradation of lipopolysaccharide of the bacterium Providencia alcalifaciens O5 followed by gel chromatography and ion-exchange chromatography or treatment with anhydrous hydrogen fluoride. On the basis of full acid hydrolysis, methylation, and 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), H-detected heteronuclear 1H,13C single-quantum coherence (HSQC), and nuclear Overhauser effect spectroscopy (NOESY), the following structure of the linear tetrasaccharide repeating unit of the polysaccharide was established:

Carbohydrate Conformation↗

PubMed1999

Anionic carbohydrate-containing polymers of cell walls in two streptoverticille genospecies.

The cell walls of two streptoverticille genospecies which belong to a historically isolated group of the genus Streptomyces contain anionic polymers of different structure. Streptomyces hachijoensis VKM Ac-191T and Streptomyces cinnamoneus subsp. azacoluta VKM Ac-606T assigned to one genospecies on the basis of DNA--DNA hybridization [5] contain 37% of an identical sugar-1-phosphate polymer. The repeating disaccharide units of the polymer, 2-amino-2-deoxy-alpha-D-glucopyranosyl-(1-->6)-2-acetamido-2-deoxy-al pha-D-glucopyranose, are linked at C-1 and C-6' by phosphodiester bonds. The cell walls of Streptomyces biverticillatus VKM Ac-891T and Streptomyces baldaccii VKM Ac-821T, members of another genospecies, contain about 30% 1,3-poly(glycerol phosphate) completely substituted by 2-amino-2-deoxy-alpha-D-glucopyranosyl residues at C-2. Due to the presence of an amino sugar with a free amino group in the repeating unit, the polymers exhibit neutral properties. Polymer structures were determined by chemical methods and NMR spectroscopy. The data indicate taxonomic specificity of anionic polymers in streptoverticille cell walls.

Carbohydrates↗

PubMed1999

Structure of the O-polysaccharide of the lipopolysaccharide of Pseudomonas syringae pv. garcae ICMP 8047.

The composition and structure of the O-polysaccharide of the lipopolysaccharide of Pseudomonas syringae pathovar garcae ICMP 8047 were studied using methylation analyses, Smith degradation, and 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), nuclear Overhauser effect spectroscopy (NOESY), and H-detected 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments. The polysaccharide was found to contain L-rhamnose and 3-acetamido-3, 6-dideoxy-D-galactose (D-Fuc3NAc) in the ratio 4:1 and to consist of two types of pentasaccharide repeating units. The major (1) and minor (2) repeating units differ from each other only in the position of substitution of one of the rhamnose residues in the main chain. Similar structural heterogeneity has been reported formerly in O-polysaccharides of some other P. syringae strains having a similar monosaccharide composition. A Fuc3NAc residue is attached to the main rhamnan chain as a side chain by a (alpha1-->4) glycosidic linkage; this has not hitherto been described in P. syringae: [figure].

Carbohydrate Conformation↗

PubMed1999

A teichoic acid of Nocardioides albus VKM Ac-805T cell walls.

A teichoic acid of Nocardioides albus VKM Ac-805T cell walls, a typical species of the genus Nocardioides, contains a poly(glycosylglycerol phosphate). The repeating unit of the polymer has the structure: [figure]. These units are in phosphodiester linkage at C-3 of glycerol and C-3 of beta-D-galactopyranose. beta-D-Galactopyranosyl residues are substituted at C-4 by beta-D-glucopyranose carrying a 4,6-pyruvate ketal group in S-configuration. The presence of pyruvic acid in the majority of repeating units increases the anionic properties of the polymer in comparison with most other common teichoic acids. This is the first report of the occurrence of a beta-D-galactofuranosyl residue in teichoic acids; it probably acts as a terminator of an extending chain of the polymer. The ratio of beta-D-galactopyranosyl to beta-D-galactofuranosyl units is 7:1. The polymer structure was determined by NMR spectroscopy. This type of teichoic acid structure has not been reported previously.

Actinomycetales↗

PubMed1998

Structural and serological studies on a new acidic O-specific polysaccharide of Proteus vulgaris O32.

The following structure of the O-specific polysaccharide chain (O-antigen) of the Proteus vulgaris 032 lipopolysaccharide (LPS) was established by 1H-NMR and 13C-NMR spectroscopy, including two-dimensional NOESY and H-detected 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments: -->2)-alpha-L-RhapI-(1-->2)-alpha-L-RhapII-(1-->4)-beta-D-++ +GalpA(I)-(1-->3)-beta-D-GlcpNAc-(1-->4)-alpha-D-GalpA(II)-(1-- >. In addition, an O-acetyl group was detected, which, most probably, is located at position 3 of a part of RhapI residues. Serological studies, using rabbit polyclonal anti-(P. vulgaris 032) serum, homologous and heterologous Proteus O-antigens and related artificial antigens, revealed the importance of an a-D-GalA-associated epitope in manifesting the immunospecificity of P. vulgaris 032 and substantiated serological relationships between the O-antigen studied and those of some other Proteus strains.

Carbohydrate Conformation↗

PubMed1998

Structure of the O-antigen of Vibrio cholerae O155 that shares a putative D-galactose 4,6-cyclophosphate-associated epitope with V. cholerae O139 Bengal.

The O-specific polysaccharide of Vibrio cholerae 0155 was studied by sugar and methylation analyses, dephosphorylation with 48% hydrofluoric acid, 1H- and 13C-NMR spectroscopy, including two-dimensional COSY, TOCSY, NOESY, and heteronuclear single-quantum coherence (HSQC) experiments. The following structure of the pentasaccharide repeating unit of the polysaccharide was established: carbohydrate sequence [see text]. An unusual component, D-galactose 4,6-cyclophosphate, has been reported previously as a component of the capsular polysaccharide and O-antigen of V. cholerae O139 Bengal and appears to be responsible for the known serological cross-reactivity between V. cholerae O139 and O155.

Carbohydrate Conformation↗

PubMed1998

Structure and cross-reactivity of the O-specific polysaccharide of Proteus penneri strain 26, another neutral Proteus O-antigen containing 2-acetamido-2,6-dideoxy-L-glucose (N-acetyl-L-quinovosamine).

A neutral O-specific polysaccharide obtained from the lipopolysaccharide of Proteus penneri strain 26 was studied using sugar analysis and 1H and 13C NMR spectroscopy, including two-dimensional NMR techniques. The following structure of the trisaccharide repeating unit was established: -->6)-alpha-D-GlcpNAc-(1-->3)-alpha-L-QuipNAc-(1-->3)-alpha-D-Glcp NAc-(1--> where L-QuiNAc is 2-acetamido-2,6-dideoxy-L-glucose (N-acetyl-L-quinovosamine). Cross-reactivity of the Proteus penneri 26 anti-O serum with other strains of P. penneri isolated in Poland and USA and one strain of P. vulgaris is discussed.

Acetylglucosamine↗

PubMed1998

Immunochemical studies of the lipopolysaccharide O-specific polysaccharide of Hafnia alvei PCM 1199 related to H. alvei PCM 1205.

On the basis of chemical analyses and NMR spectroscopic studies, it was found that the O-specific polysaccharide (O-PS) isolated from the Hafnia alvei PCM 1199 lipopolysaccharide (LPS) is a glycerol teichoic-acid-like polymer having a repeating unit of the following structure: [structure in text] where Qui4NAc is 4-acetamido-4,6-dideoxyglucose and O-acetylation at both positions is non-stoichiometric. The glycosidic linkage of the lateral beta-D-GlcpNAc residue is acid-labile and cleaved from the O-PS during mild acid hydrolysis or dephosphorylation with 48% hydrofluoric acid. Comparative analysis revealed that the structure of the H. alvei PCM 1199 O-PS is similar to that of H. alvei PCM 1205, which differs in the presence of an additional lateral alpha-D-Glcp residue and the position of one of the O-acetyl groups only. Accordingly, serological tests revealed a high degree of serological similarity between LPSs and O-PSs of the two H. alvei strains.

Carbohydrate Conformation↗

PubMed1998

Somatic antigens of pseudomonads: structure of the O-specific polysaccharide of Pseudomonas fluorescens biovar B, strain IMV 247.

The O-specific polysaccharide of Pseudomonas fluorescens biovar B, strain IMV 247, was studied by acid hydrolysis, GLC-MS and 1H and 13C NMR spectroscopy, including 1D and 2D NOE, 2D hybrid TOCSY and ROESY (TORO), and 2D H-detected heteronuclear multiple-bond correlation (HMBC) experiments. The polysaccharide was found to contain L-rhamnose, 3.6-dideoxy-3-[(S)-3-hydroxybutyramido]-D-glucose (D-Qui3NHb), 2-acetamido- 2,4,6-trideoxy-4-[(S)-3-hydroxybutyramido-D-glucose (D-QuiNAc4NHb) and 2-acetamido-2- deoxy-D-galacturonic acid (D-GalNAcA). Partial acid hydrolysis of the polysaccharide resulted in a non-reducing GalNAcA-->QuiNAc4NHb disaccharide with the 3-hydroxybutyryl group glycosylated intramolecularly by the QuiN4N residue. The following structure of the tetrasaccharide repeating unit of the polysaccharide was established:-->4) -alpha-D-GalpNAcA-(1-->3)- alpha-D-QuipNAc4NHb-(1-->2)-beta-D-Quip3NHb-(1-->2)-alpha-L- Rhap(1-->.

Carbohydrate Conformation↗

PubMed1998

Structure of the O-specific polysaccharide of Citrobacter freundii O3a,3b,1c.

The following structure of the O-specific polysaccharide of Citrobacter freundii O3a,3b,1c containing D-mannose and D-rhamnose was established using sugar analysis and NMR spectroscopy, including computer-assisted analysis of the 13C NMR spectrum, 2D COSY, H,H-relayed COSY, heteronuclear 13C, 1H correlation (HETCOR), and rotating-frame NOE spectroscopy (ROESY):-->4)-alpha-D-Manp-(1-->3)-beta-D-Rhap-(1-->4) -beta-D-Rhap-(1-->.

Carbohydrate Sequence↗

PubMed1998

Structure of a highly acidic O-specific polysaccharide of lipopolysaccharide of Pseudoalteromonas haloplanktis KMM 223 (44-1) containing L-iduronic acid and D-QuiNHb4NHb.

An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide isolated by phenol-water extraction of Pseudoalteromonas haloplanktis strain KMM 223 (44-1). L-Iduronic acid (IdoA) was found to be a component of the polysaccharide and identified by NMR spectroscopy and after carboxyl-reduction followed by acid hydrolysis and acetylation, by GLC-MS as 2,3,4-tri-O-acetyl-1,6-anhydroidose. On the basis of 1H and 13C NMR spectroscopic studies, including 1D NOE, 2D NOESY, HSQC and HMBC experiments, the following structure of the branched pentasaccharide repeating unit of the polysaccharide was established: -->4)-beta-D-GlcpAI-(1-->4)-beta-D-GlcpAII-(1-->3)-beta-D-++ +QuipNHb4NHbII- (1-->2)-alpha-L-IdopA-(-->4 increases 1 alpha-D-QuipNAc4NAcI where QuiNAc4NAc and QuiNHb4NHb are 2,4-diacetamido-2,4,6-trideoxyglucose and 2,4,6-tri-deoxy-2,4- di[(S)-3-hydroxybutyramido]glucose, respectively. This is the first report of L-iduronic acid in a lipopolysaccharide and of D-QuiNHb4NHb in nature.

Carbohydrate Sequence↗

PubMed1998

Identification of N epsilon-[(R)-1-carboxyethyl]-L-lysine in, and the complete structure of, the repeating unit of the O-specific polysaccharide of Providencia alcalifaciens O23.

N epsilon-[(R)-1-Carboxyethyl]-L-lysine was released by acid hydrolysis from the O-specific polysaccharide of Providencia alcalifaciens O23 and identified by 1H and 13C NMR spectroscopy, GLC-MS after conversion to a di-N-acetylated dimethyl ester, and by comparison with the authentic sample. Solvolysis of the polysaccharide with anhydrous HF resulted in an amide of D-glucuronic acid with N epsilon-[(R)-1-carboxyethyl]-L-lysine. These and published data allowed the determination of the full structure of the repeating unit of the O-specific polysaccharide.

Carbohydrate Conformation↗

PubMed1998

Structure of the acidic polysaccharide chain of the lipopolysaccharide of Shewanella alga 48055.

A lipopolysaccharide (LPS) with an acidic polysaccharide chain was isolated from the bacterium Shewanella alga strain 48055 and cleaved selectively at the glycosidic linkage of N-acetylneuraminic acid to give a tetrasaccharide. Studies of the tetrasaccharide and the O-deacylated LPS by 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, NOESY, rotating-frame NOE spectroscopy (ROESY), and H-detected 1H, 13C heteronuclear multiple-quantum coherence (HMQC) experiments, revealed the following structure of the polysaccharide repeating unit: -->3)-beta-D-GalpA6GroN-(1-->3)-beta-D-GlcpNAc-(1-->3)-alpha-D- GalpA6GroN- (1-->4)-alpha-Neup5Ac-(2--> where GroN is an amidically linked residue of 2-amino-1,3-propanediol (2-amino-2-deoxyglycerol). A similar structure, but with 2-acetamido-2,6-dideoxy-D-glucose instead of 2-acetamido-2-deoxy-D-glucose, has been reported previously for the polysaccharide chain of a non-O1 Vibrio cholerae H11 LPS [E. V. Vinogradov, O. Holst, J.E. Thomas-Oates, K.W. Broady, and H. Brade, Eur. J. Biochem., 210 (1992) 491-498].

Carbohydrate Conformation↗

PubMed1998

Structure of the O-specific polysaccharide of a serologically separate Proteus penneri strain 22.

The O-specific polysaccharide chain (O-antigen) of Proteus penneri strain 22 lipopolysaccharide was studied using chemical methods, including partial acid hydrolysis and Smith degradation, as well as one- and two-dimensional 1H and 13C NMR spectroscopy. The following structure of the pentasaccharide repeating unit was established: [sequence: see text] The O-specific polysaccharide contains a GalNAc residue in the furanose form which has not been hitherto found in bacterial polysaccharides. The O-antigen studied is serologically and structurally unique among Proteus strains and, therefore, a new Proteus serogroup O63 is proposed for P. penneri strain 22.

Carbohydrate Conformation↗