Structure of the O-specific polysaccharide of Citrobacter braakii O7a,3b,1c.

The following structure of the O-specific polysaccharide of Citrobacter braakii O7a,3b,1c was established using sugar and methylation analyses and NMR spectroscopy, including 2D COSY, TOCSY, NOESY, and 1H, 13C heteronuclear single-quantum coherence (HSQC) experiments: (struture: see text). The main D-mannan chain of the polysaccharide studied has the same structure as the O-specific polysaccharide of Escherichia coli O9, Klebsiella pneumoniae O3, and Hafnia alvei PCM 1223.

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:

Pseudomonas aeruginosa antigens as potential vaccines.

Pseudomonas aeruginosa is one of the most important opportunistic bacterial pathogens in humans and animals. This organism is ubiquitous and has high intrinsic resistance to antibiotics due to the low permeability of the outer membrane and the presence of numerous multiple drug efflux pumps. Various cell-associated and secreted antigens of P.

R-form lipopolysaccharides (LPS) of Gram-negative bacteria as possible vaccine antigens.

The antigenic and immunogenic properties of R-form lipopolysaccharides (LPS) of Pseudomonas aeruginosa, Salmonella spp., Escherichia coli and Shigella spp. were studied.

Structure of the O-specific polysaccharide of the bacterium Providencia alcalifaciens O23 containing a novel component: an amide of D-glucuronic acid with N(epsilon)-(1-carboxyethyl)lysine.

An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of the bacterium Providencia alcalifaciens O23 and found to contain D-glucose, D-galactose, 2-acetamido-2-deoxy-D-galactose, and N epsilon-(1-carboxyethyl)-N alpha-(D-glucuronoyl)lysine. On the basis of full and partial acid hydrolyses, selective solvolysis with anhydrous hydrogen fluoride, and 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), H-detected heteronuclear 1H, 13C multi-quantum coherence (HMQC), and rotating-frame nuclear Overhauser effect spectroscopy (ROESY), the following structure of the liner tetrasaccharide repeating unit of the polysaccharide was established [structure: see text]

Structural and serological studies of lipopolysaccharides of Citrobacter O35 and O38 antigenically related to Salmonella.

Structural analysis using 13C NMR spectroscopy and methylation showed that lipopolysaccharides (LPSs) of Citrobacter freundii O35 and Salmonella arizonae O59 have structurally identical O-specific polysaccharide chains, and those of C. freundii O38 and Salmonella kentucky differ only in the presence of O-acetyl groups in the former. Serological relationships between the structurally similar LPSs were demonstrated using inhibition of ELISA, rocket immunoelectrophoresis, double gel diffusion, and immunoblotting.

Mouse protection induced by Pseudomonas aeruginosa PAC1R and its defective mutants, Salmonella minnesota Re-mutant and Escherichia coli O14.

Pseudomonas aeruginosa PAC1R and its defective mutants (acetone-killed bacteria), Salmonella minnesota Re mutant (acetone-killed bacteria and Re-LPS) and Escherichia coli O14 (acetone-killed bacteria and enterobacterial common antigen, ECA) were studied in a mouse active protection test. Immunized mice were challenged with wild-type P. aeruginosa strains.

The structure of the O-specific polysaccharide of Salmonella arizonae O21 (Arizona 22) containing N-acetylneuraminic acid.

The O-specific polysaccharide of S. arizonae O21 was found to contain 2-acetamido-2-deoxy-D-glucose, 2-acetamidino-2,6-dideoxy-L-galactose, N-acetylneuraminic acid, and O-acetyl groups. On the basis of 1H and 13C NMR studies of the intact and O-deacetylated polysaccharide and oligosaccharide fragments obtained by solvolysis with anhydrous hydrogen fluoride, partial methanolysis and partial hydrolysis, it was concluded that the O-specific polysaccharide has the following structure: [formula: see text]

The structure of the O-specific polysaccharide of Citrobacter O16 containing glycerol phosphate.

The O-specific polysaccharide, obtained by mild acid degradation of Citrobacter O16 lipopolysaccharide, consists of D-glucose, D-galactose, 2-acetamido-2-deoxy-D-galactose, glycerol and phosphate in the ratios 2:2:2:1:1. Selective cleavage of the polysaccharide was carried out by Smith degradation, N-deacetylation-deamination and dephosphorylation with 48% hydrofluoric acid, which was accompanied by unexpected splitting of one of the glycosidic linkages. The structures of the oligosaccharides thus obtained were established using 1H- and 13C-NMR spectroscopy, including one-dimensional NOE, two-dimensional rotating-frame NOE, homonuclear and heteronuclear 13C, 1H correlation spectroscopy, and, for the Smith degradation product, positive- and negative-ion-mode fast-atom-bombardment MS and MS/MS with collision-induced dissociation.

Immunological studies of an artificial antigen with specificity of a common polysaccharide antigen of Pseudomonas aeruginosa.

Synthetic D-rhamnan, with the structure of Pseudomonas aeruginosa common polysaccharide antigen (CPA), was conjugated with BSA. The artificial antigen obtained, and the natural antigens, lipopolysaccharides (LPS) of P. aeruginosa and Pseudomonas cerasi with rhamnan chains of the same structure, were studied by ELISA with rabbit antibodies to the D-rhamnan-BSA conjugate and to the P.

Structure of the O-specific polysaccharide of Salmonella arizonae O45.

The O-specific polysaccharide of Salmonella arizonae O45 (Arizona 11) is acidic and has a branched hexasaccharide repeating unit containing two residues of L-fucose, one residue each of D-galactose, D-ribose, D-glucuronic acid, and 2-acetamido-2-deoxy-D-glucose, and an O-acetyl group. It was studied with the help of 1H and 13C NMR spectroscopy, including 1D selective spin-decoupling and homonuclear Hartmann-Hahn spectroscopy, 2D homonuclear and 13C-1H heteronuclear shift-correlated (COSY) and NOE (ROESY) spectroscopy, as well as by methylation analysis, and selective cleavages with anhydrous HF (or dilute HCl) and lithium in ethylenediamine to yield two different tetrasaccharide fragments. As a result, the following structure of the polysaccharide was established: [formula: see text] Anomalous 13C chemical shifts were observed in the spectrum of the trisaccharide fragment alpha-L-Fucp-(1-->2)-beta-D-Gal p-(1-->3)-beta-D-Glc pNAc, structurally related to the Le(d) blood-group determinant, and rationalised by inter-residue proton-proton interactions.

Specific and non-specific mouse protection induced by different chemotypes of the Pseudomonas aeruginosa lipopolysaccharides.

Lipopolysaccharides (LPS) of Pseudomonas aeruginosa were studied by the mouse active, cross-protection test. The primary structure of O-specific polysaccharides (O-repeating units) of different chemotypes was determined and their cross-protective activity demonstrated. Low doses of LPS (0.

The structure of the O-specific polysaccharide chain of the lipopolysaccharide of Salmonella arizonae O61.

The O-specific polysaccharide was obtained by mild degradation of the Salmonella arizonae O61 lipopolysaccharide with acid. It contained 2-acetamido-2-deoxy-D-glucose, 2-acetamidino-2,6-dideoxy-L-galactose (FucAm), and 7-acetamido-3,5,7,9-tetradeoxy-5-[(R)-3-hydroxybutyramido]-D- glycero-L-galacto-nonulosonic acid (Sug). On the basis of partial acid hydrolysis with 0.

Antibodies against the common polysaccharide and protein protective antigens of Pseudomonas aeruginosa in normal blood donors.

Screening of normal plasma obtained from 172 blood donors from the Helsinki area and from 46 blood donors from the Moscow area was performed in order to reveal 'natural' antibodies to the common polysaccharide (rhamnan) and protein antigens of P. aeruginosa. Antibodies were detected by ELISA.

Clinico-immunological trials of Pseudomonas aeruginosa vaccine.

Pseudomonas aeruginosa vaccine (PV) containing predominantly cell-wall protein protective antigens was tested for safety and immunogenicity by immunization of 119 volunteers. The criteria for safety and immunogenicity were the absence of serious post-vaccinal reactions or complications either during immunization or 12 months later. There were mild (19 donors or 15.

Detection of common polysaccharide antigen of Pseudomonas aeruginosa with O-antiserum to Pseudomonas cerasi.

The identity of the structures of common polysaccharide antigen (CPA) of Pseudomonas aeruginosa and O-antigen of Pseudomonas cerasi was used for immunochemical study of polysaccharide antigens of seven immunotypes (IT) of P. aeruginosa. ELISA performed with O-antiserum to P.

Experimental studies on the protective efficacy of a Pseudomonas aeruginosa vaccine.

Pseudomonas aeruginosa vaccine (PV) containing cell proteins with molecular weight (Mr) 20,000-100,000 and up to 0.08% (w/v) admixture of lipopolysaccharide was obtained by water-salt extraction and subsequent ultrafiltration. PV protects mice against experimental P.

Saccharides of seven Pseudomonas aeruginosa immunotypes.

The structures of O-specific polysaccharides obtained by mild acid degradation of lipopolysaccharides (LPS) from seven Pseudomonas aeruginosa Fisher's immunotypes have been studied. The polysaccharides consist mainly of monoamino and diamino sugars, frequently also carrying acidic functions. Some of the sugars were detected in nature for the first time in these organisms.

Somatic antigens of Pseudomonas aeruginosa. The structure of O-specific polysaccharide chains of lipopolysaccharides of P. aeruginosa O3 (Lányi), O25 (Wokatsch) and Fisher immunotypes 3 and 7.

O-specific polysaccharides, obtained on mild acid degradation of lipopolysacchrides of the serologically related strains Pseudomonas aeruginosa O3 (Lányi classification), O25 (Wokatsch classification) and immunotypes 3 and 7 (Fisher classification), are built up of trisaccharide repeating units involving 2-acetamido-2,6-dideoxy-D-galactose (N-acetyl-D-fucosamine), 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid or 2,3-diacetamido-2,3-dideoxy-L-guluronic acid and 3-acetamidino-2-acetamido-2,3-dideoxy-D-mannuronic acid or 3-acetamidino-2-acetamido-2,3-dideoxy-L-guluronic acid. Lányi O3(a),3d,3f and Wokatsch O25 polysaccharides contain also O-acetyl groups. On the basis of solvolysis with anhydrous hydrogen fluoride, resulting in trisaccharide fragments with N-acetylfucosamine residue at the reducing terminus, chemical modifications of the acetamidino group (alkaline hydrolysis to the acetamido group or reductive deamination to the ethylamino group), as well as analysis by 1H-NMR (including nuclear Overhauser effect experiments) and 13C-NMR spectroscopy, and fast-atom bombardment mass spectrometry, it was concluded that the repeating units of the polysaccharides have the following structures: (Formula: see text) where HexNAcAmA = alpha-L-GulNAcAmA (approximately 70%) or beta-D-ManNacAMA (approximately 30%).

Somatic antigens of Pseudomonas aeruginosa. The structure of O-specific polysaccharide chains of the lipopolysaccharides from P. aeruginosa II (Sandvik) and V (IM-1, Verder-Evans).

The lipopolysaccharides from two serologically related strains of Pseudomonas aeruginosa II (Sandvik classification) and V (IM-1, Verder-Evans classification) were isolated by the Westphal method and cleaved with 1% acetic acid. The O-specific polysaccharide from Sandvik II lipopolysaccharide involved L-rhamnose, N-acetyl-D-quinovosamine, and N-acetyl-D-galactosaminuronic acid in the ratio 2:1:1, as well as O-acetyl groups. The Verder-Evans V O-specific polysaccharide was found to contain just the same sugars and, in addition, D-glucose, the monosaccharide ratio being 2:1:1:1.

Somatic antigens of Pseudomonas aeruginosa. The structure of O-specific polysaccharide chains of the lipopolysaccharides from P. aeruginosa O5 (Lányi) and immunotype 6 (Fisher).

Lipopolysaccharides were isolated from dry bacterial cells of Pseudomonas aeruginosa O5a,b,c, O5a,b,d, O5a,d (Lányi classification) and immunotype 6 (Fisher classification) by the Westphal procedure. Their polysaccharide chains were built up of trisaccharide repeating units containing D-xylose, 2-acetamido-2,6-dideoxy-D-galactose and a new sialic acid-like sugar, the di-N-acyl derivative of 5,7-diamino-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic (pseudaminic) acid. Formyl, acetyl and (R)-3-hydroxybutyryl groups were identified as the N-acyl substituents of the last monosaccharide; O5a,b,c and O5a,b,d lipopolysaccharides also contained O-acetyl groups.