[Specific structural features and immunomodulatory properties of the lipopolysaccharides of Pseudomonas bacteria].

The results of in vitro studies of the immunomodulatory action of the lipopolysaccharides (LPS) of the Pseudomonas bacteria--P. fluorescens biovar I strains IMV 4125 = ATCC 13525, IMV 7769, and IMV 1152; P. fluorescens biovar IV strain IMV 2111; P. syringae pv. syringae IMV 281 = CPPB 281 = ATCC 19310 and IMV 467; and P. wieringae IMV 7923--on the mouse spleenocytes and human peripheral blood mononuclear cells (PBMC), B lymphocytes, and T lymphocytes are described. The proliferative activity of mouse spleenocytes correlated with the degree of LPS toxicity. The PBMC mitogenic activity induced by the P. fluorescens IMV 7769 LPS preparation exceeded the activity of E. coli 026:B6 LPS. The immunomodulatory effect of LPS on T cells was strain and dose dependent. The LPS of P. syringae pv. syringae INV 467 displayed a comparatively pronounced immunomodulatory effect on human blood B lymphocytes.

[Composition, structure, and biological properties of lipopolysaccharides from different strains of Pseudomonas syringae pv. atrofaciens].

The composition, structure, and certain biological properties of lipopolysaccharides (LPS) isolated from six strains of bacteria Pseudomonas syringae pv. atrofaciens pathogenic for grain-crops (wheat, rye) are presented. The LPS-protein complexes were isolated by a sparing procedure (extraction from microbial cells with a weak salt solution). They reacted with the homologous O sera and contained one to three antigenic determinants. Against the cells of warm-blooded animals (mice, humans) they exhibited the biological activity typical of endotoxins (stimulation of cytokine production, mitogenetic activity, etc.). The LCD of the biovar type strain was highly toxic to mice sensitized with D-galactosamine. The structural components of LPS macromolecules obtained by mild acidic degradation were characterized: lipid A, core oligosaccharide, and O-specific polysaccharide (OPS). Fatty acids 3-HO-C10:0, C12:0, 2-HO-C12:0, 3-HO-C12:0, C16:0, C16:1, C18:0, and C18:1 were identified in lipid A of all the strains, as well as the components of the hydrophilic part: glucosamine (GlcN), ethanolamine (EtN), phosphate, and phosphoethanolamine (EtN-P). In the core LPS, glucose (Glc), rhamnose (Rha), L-glycero-D-manno-heptose (Hep), GlcN, galactosamine (GalN), 2-keto-3-deoxy-D-mannooctonic acid (KDO), alanine (Ala), and phosphate were present. The O chain of all the strains consisted of repeated elements containing a linear chain of three to four L- (two strains) or D-Rha (four strains) residues supplemented with a single residue of 3-acetamido-3,6-dideoxy-D-galactose (D-Fucp3Nac), N-acetyl-D-glucosamine (D-GlcpNAc), D-fucose (D-Fucf), or D-Rhap (strain-dependent) as a side substitute. In different strains the substitution position for Rha residues in the repeated components of the major rhamnan chain was also different. One strain exhibited a unique type of O-chain heterogeneity. Immunochemical investigation of the LPS antigenic properties revealed the absence of close serological relations between the strains of one pathovar; this finding correlates with the differences in their OPS structure. Resemblance between the investigated strains and other P. syringae strains with similar LPS structures was revealed. The results of LPS analysis indicate the absence of correlation between the OPS structure and the pathovar affiliation of the strains.

[Characterization of lipopolysaccharides from Pseudomonas fluorescens IMB 2108 (biovar II) and IMB 2111 (biovar IV) with O-chains represented by alpha-glucan].

Results of studies of the structurally unique O-chains of lipopolysaccharides, which were isolated from the dry biomass of Pseudomonas fluorescens IMB 2108 (biovar II) and IMB 2111 (biovar IV) by the Westphal technique and purified by repeated ultracentrifugation, are reported. The bulk of the lipopolysaccharide preparations contained S- and R-molecules at an average molar ratio of 1: 2. The main components of the hydrophobic moiety of lipid A were 3-hydroxydecanoic, 2-hydroxydodecanoic, 3-hydroxydodecanoic, dodecanoic, hexadecanoic, and octadecanoic acids, as well as hexadecenoic and octadecenoic acids. Glucosamine and phosphoethanolamine were identified as components of the hydrophilic moiety of lipid A. The degree of lipid A phosphorylation amounted to 3-4%. Fractions of the core oligosaccharide contained glucose, galactose, mannose, rhamnose, arabinose, glucosamine (only in strain IMB 2108), alanine, phosphoethanolamine, phosphorus, and 2-keto-3-deoxyoctulosonic acid (KDO). Heptose was present in trace amounts. O-specific polysaccharide chains were represented by a linear polymer of D-glucose units, which were linked together via alpha-(1,4) glycoside bonds. The existence of P. fluorescens strains that have alpha-1,4-glucan as the O-chain of their lipopolysaccharides has not been described before.

[Characterization of the lipopolysaccharide from Rahnella aquatilis 1-95].

The lipopolysaccharide from the freshwater bacterium Rahnella aquatilis 1-95 has been isolated and investigated for the first time. The structural components of the lipopolysaccharide molecule: lipid A, core oligosaccharide, and O-specific polysaccharide were isolated by mild acidic hydrolysis. In lipid A, 3-hydroxytetradecanoic and tetradecanoic acids were found to be the predominant fatty acids. In the core oligosaccharide, galactose, arabinose, fucose, and an unidentified component were shown to be the major monosaccharides. The O-specific polysaccharide consists of a regularly repeating trisaccharide unit with the acyl and phosphate following structure: [structure: see text] groups have been shown to be responsible for the toxic and pyrogenic properties of the lipopolysaccharide of R. aquatilis.

[Structural characteristics and biological properties of Pseudomonas fluorescens lipopolysaccharides].

The structure and biological properties of lipopolysaccharides (LPSs) from strains IMB 4125 (=ATCC 13525) and IMB 7769 of the bacterium Pseudomonas fluorescens (biovar I) were studied in vitro. LPSs were similar in the composition of lipid A and the core lipid but differed in the structure of O-specific polysaccharide chains, which was corroborated by the absence of serological relationships between them. The toxicity (LD50) of LPSs of P. fluorescens with respect to D-glucosamine-sensitized mice was 40-50 times lower than the toxicity of the classic endotoxins, LPSs of E. coli. The LPSs studied stimulated the production of tumor necrosis factor (TNF) and nitric oxide (NO) by mouse peritoneal macrophages. The rates of TNF and NO synthesis induced by the LPSs of interest were eight to nine and three to five times lower, respectively, than the corresponding parameters of the control LPSs of E. coli 055:B5 and 026:B6. Additionally, LPS preparations of the P. fluorescens strains induced TNF synthesis by monocytes of human whole-blood preparations. Certain differences in biological properties of these strains have been revealed, which could be due to the characteristic features of LPS structure and composition in different cultures.

[A comparative analysis of the ice nucleation activity of pseudomonad cells and lipopolysaccharides]. / Sravnitel'nyi analiz l'doobrazuiushchikh svoistv kletok i lipopolisakharidov bakterii roda Pseudomonas.

The paper deals with the study of the ice nucleation activity of the cells, extracellular lipopolysaccharides (ELPSs), lipopolysaccharides (LPSs), and their structural components (lipid A, core oligosaccharide, and O-specific polysaccharide) of Pseudomonas fluorescens, P. syringae, P.fragi, and P. pseudoalcaligenes. The aqueous suspensions of the intact cells of P. syringae IMV 1951 and IMV 185 began to freeze at -1 and -4 degrees C, respectively. This suggests that these cells possess ice nucleation activity. The aqueous cell suspensions of two other strains, P. fluorescens IMV 1433 and IMV 2125, began to freeze at lower temperatures than did distilled water (-9 degrees C), which suggests that the cells of these strains possess antifreeze activity. The ice nucleation activity of the bacterial strains studied did not show any correlation with their taxonomic status. The ice nucleation activity of ELPSs depended little on their concentration (within a concentration range of 0.2-0.4%). In most cases, the ice nucleation activity of ELPSs, LPSs, and their structural components differed from that of the intact cells from which these biopolymers were obtained. This may indicate that the biopolymers under study play a role in ice nucleation, but this role is not crucial. The relationship between the structure of LPSs and their effect on ice nucleation is discussed.

[Structure and properties of the lipopolysaccharide of Pseudomonas fluorescens IMV 2366 (biovar III)]. / Stroenie i svoistva lipopolisakkharida Pseudomonas fluorescens IMV 2366 (biovar III).

The lipopolysaccharide (LPS) preparation isolated from the bacterial mass of Pseudomonas fluorescens IMV 2366 (biovar III) by Westphal's method and purified by repeated ultracentrifugation was characterized by the presence of the S- and R-forms of molecules. The following structural portions of the LPS molecule were obtained in the individual state and characterized: lipid A, core oligosaccharide, and O-specific polysaccharide. The main components of the lipid A hydrophobic moiety were 3-hydoxydecanoic, 2-hydroxydodecanoic, 3-hydroxydodecanoic, dodecanoic, and hexadecanoic fatty acids. Glucosamine, phosphoethanolamine, and phosphorus were identified as the components of the lipid A hydrophilic moiety. Rhamnose, glucose, galactose, glucosamine, galactosamine, alanine, phosphoethanolamine, phosphorus, 2-keto-3-desoxyoctulosonic acid (KDO), as well as 2-amino-2,6-didesoxygalactose (FucN) and 3-amino-3,6-didesoxyglucose (Qui3N), were revealed in the composition of the core oligosaccharide fractions. O-specific polysaccharide chains were established to be composed of repeating trisaccharide units consisting of residues of L-rhamnose (L-Rha), 2-acetamido-2,6-didesoxy-D-galactose (D-FucNAc), and 3-acylamido-3,6-didesoxy-D-glucose (D-Qui3NAcyl), where Acyl = 3-hydroxy-2,3-dimethyl-5-hydroxyprolyl. Neither double immunodiffusion in agar not the immunoenzyme assay revealed serological relations between the strain studied and the P. fluorescens strains studied earlier.

[Chemical and biological characterization of lipopolysaccharides from the Pseudomonas syringae pv. maculicola IMV 381 collection culture and its dissociants]. / Khimiko-biologicheskaia kharakteristika lipopolisakharidov iz kollektsionnoi kul'tury Pseudomonas syringae pv. maculicola IMV 381 i ee dissotsiantov.

Lipopolysaccharides (LPS) were isolated from the crude bacterial mass of the Pseudomonas syringae pv. maculicola IMV 381 collection culture and its virulent and avirulent subcultures isolated earlier from the heterogeneous collection culture due to its natural variability during long-term storage. The composition, immunochemical properties, and certain parameters of the biological activity of the LPS preparations obtained were studied. The structural parts of the LPS macromolecule--lipid A, the core oligosaccharide, and O-specific polysaccharide (OPS)--were isolated and characterized. The following fatty acids were identified in the lipid A composition of all cultures: 3-OH-C10:0, C12:0, 2-OH-C12:0, 3-OH-C12:0, C16:1, C16:0, C18:1, and C18:0. Glucosamine (GlcN), ethanolamine (EtN), phosphoethanolamine (EtN-P), and phosphorus (P) were revealed in the hydrophilic portion of the macromolecule. In the core portion of the LPS macromolecule, glucose (Glc), rhamnose (Rha), GlcN, galactosamine (GalN), 2-keto-3-deoxyoctulosonic acid (KDO), alanine (Ala), and P were found. The peculiarities of the structure of LPS isolated from the stable collection culture (LPS(stab)) and its virulent (LPS(vir)) and avirulent (LPS(air)) subcultures were studied. LPS(vir) and LPS(avir) were identical in the monosaccharide composition and contained as the main components L-rhamnose (L-Rha) and 3-acetamido-3,6-dideoxy-D-galactose (D-Fuc3NAc), like LPS(stab) studied earlier. The NMR spectra of LPS(vir) were identical to the spectra of LPS(stab), whose O-chain repeating unit structure was studied by us earlier, whereas LPS(avir) differed from LPS(vir) in the NMR spectrum and was identified by us as the SR form. LPS(avir) was serologically identical to LP(stab) and LPS(vir). Hence, the degree of polymerism of the LPS O-chain of P. syringae pv. maculicola IMV 381 is the main virulence factor in the infected model plants. Serological relationships were studied between P. syringae pv. maculicola IMV 381 and the strains of other pathovars with structurally similar LPS.

[Some characteristics of Pseudomonas syringae pv. maculicola dissociants]. / Nekotorye kharakteristiki dissotsiantov Pseudomonas syringae pv. maculicola.

Pseudomonas syringae pv. maculicola dissociants producing colonies of different morphotype were found to possess similar biochemical and serological properties but different virulence to the host plant. The heterogeneous extracellular and intracellular lipopolysaccharide-protein complexes of the dissociants differed in their chemical composition and biological activity towards test plants.

Structural heterogeneity in the lipopolysaccharides of Pseudomonas syringae with O-polysaccharide chains having different repeating units.

Studies by sugar and methylation analyses, Smith degradation, and 1H and 13C NMR spectroscopy revealed a structural heterogeneity in the O-polysaccharides of Pseudomonas syringae pvs. coronafaciens IMV 9030 and atrofaciens IMV 8281 owing to the presence of different types of repeating units. In strain IMV 9030, the major repeating units are a linear alpha-L-rhamnose trisaccharide and a tetrasaccharide (A, n=0 or 1). A minor repeating unit is a branched pentasaccharide with an alpha-L-rhamnose main chain and a lateral 3-acetamido-3,6-dideoxy-D-galactose (D-Fuc3NAc) residue (B, X=2, n=1). In strain IMV 8281, all repeating units are branched and differ in size and position of substitution of one of the alpha-L-rhamnose residues (tetrasaccharide, B, X=3, n=0; pentasaccharides, B, X=2 or 3, n=1). [structure--see text] Reinvestigation of the structure of the branched O-polysaccharide of P. syringae pv. tomato IPGR 140 showed that, together with the major tetrasaccharide repeating unit (B, X=3, n=0) [Knirel, Y. A., et al. Carbohydr. Res. 1993, 243, 199-204], it has a minor pentasaccharide repeating unit (B, X=3, n=1).

[Comparative characteristics of lipopolysaccharides of various Pseudomonas fluorescens strains (Biovar I)]. / Sravnitel'naia kharakteristika lipopolisakharidov razlichnykh shtammov Pseudomonas fluorescenns (biovar I).

From the biomass of five Pseudomonas fluorescens biovar I strains, including the P. fluorescens type strain IMV 4125 (ATCC 13525), lipopolysaccharides (LPS) were isolated (by extraction with a phenol-water mixture followed by repeated ultracentrifugation), as well as individual structural components of the LPS macromolecule: lipid A, the core oligosaccharide, and O-specific polysaccharide (O-PS). 3-Hydroxydecanoic, 2-hydroxydodecanoic, 3-hydroxydodecanoic, dodecanoic, hexadecanoic, octadecanoic, hexadecenoic, and octadecenoic fatty acids were present in lipid A of the LPS of all the strains studied. Glucosamine, ethanolamine, and phosphoethanolamine were revealed in the lipid A hydrophilic part of all of KDO, a trace amount of heptoses, ethanolamine, phosphoethanolamine, alanine, and phosphorus were identified as the main core components. Interstrain differences in the core oligosaccharide composition were revealed. Structural analysis showed that the O-PS of the type strain, as distinct from that of other strains, is heterogeneous and contains two types of repetitive units, including (1) three L-rhamnose residues (L-Rha), one 3-acetamide-3,6-dideoxy-D-galactose residue (D-Fuc3NAc) as a branching substitute of the L-rhamnan chain and (2) three L-Rha residues and two branching D-Fuc3NAc residues. The type strain is also serologically distinct from other biovar I strains due to the LPS O-chain structure, which is similar to those of the strains of the species Pseudomonas syringae, including the type strain. The data of structural analysis agree well with the results of immunochemical studies of LPS.

Characterization of the lipopolysaccharide and structure of the O-specific polysaccharide of the bacterium Pseudomonas syringae pv. atrofaciens IMV 948.

Lipopolysaccharide (LPS) was isolated from the phytopathogenic bacterium Pseudomonas syringae pv. atrofaciens IMV 948 by mild extraction of the microbial cells with saline, and the properties, composition, and structure of the LPS were studied. The LPS showed low toxicity in D- galactosamine-sensitized mice and low biological activity in plants. Structural components of LPS--lipid A, core oligosaccharide, and O-specific polysaccharide (OPS)--were obtained by mild acid degradation and characterized. The lipid A contained fatty acids 3-HO-C10:0, C12:0, 2-HO-C12:0, 3-HO-C12:0, C16:0, C16:1, C18:0, and C18:1, as well as components of the hydrophilic moiety: GlcN, ethanolamine, phosphate, and phosphoethanolamine. The LPS core contained components typical of pseudomonads: glucose, rhamnose (Rha), L-glycero-D-manno-heptose, GlcN, GalN, 2-keto-3-deoxy-D-manno-octonic acid, alanine, and phosphate. The OPS consisted of L-Rha and D-GlcNAc in the ratio 4 : 1 and was structurally heterogeneous. The main pentasaccharide repeating unit of the OPS has the following structure: [structure see text]. Immunochemical studies showed that P. syringae pv. atrofaciens IMV 948 is serologically separate from other P. syringae strains, including those that have structurally similar OPS.

[The distinctive features of the structure of the Pseudomonas fluorescens IMV 247 (biovar II) lipopolysaccharide]. / Osobennosti stroeniia lipopolisakharida Pseudomonas fluorescens IMB 247 (biovar II).

The results of the study of the Pseudomonas fluorescens IMV 247 (biovar II) lipopolysaccharide (LPS) isolated from the dry bacterial mass by Westphal's method and purified by repeated ultracentrifugation are presented. The macromolecular organization of the LPS is characterized by the presence of S and R forms of LPS molecules in a 1:1 ratio. The structural components of the LPS molecule--lipid A, the core oligosaccharide, and the O-specific polysaccharide--were isolated and characterized. 3-Hydroxydecanoic, 2-hydroxydodecanoic, 3-hydroxydodecanoic, and dodecanoic acids proved to be the main lipid A fatty acids. Glucosamine, phosphoethanolamine, and phosphorus were identified as the components of the lipid A hydrophilic portion. Glucose, galactose, arabinose, rhamnose, glucosamine, alanine, phosphoethanolamine, phosphorus, and 2-keto-3-deoxyoctulonate (KDO) were revealed in the heterogeneous fraction of the core oligosaccharide. The O-specific polysaccharide chain was composed of repeating tetrasaccharide units consisting of L-rhamnose (L-Rha), 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) residues. A peculiarity of the O-specific polysaccharide was that it released, upon partial acid hydrolysis, the nonreducing disaccharide GalNAcA-->QuiNAc4NHb with a 3-hydroxybutyryl group glycosylated intramolecularly with a QuiN4N residue. Double immunodiffusion in agar and lipopolysaccharide precipitation reactions revealed no serological interrelationship between the strain studied and the P. fluorescens strains studied earlier.

[Characteristics of lipopolysaccharide from Pseudomonas fluorescens (biovar I)]. / Kharakteristika lipopolisakharida Pseudomonas fluorescens (biovar I).

Lipopolysaccharide (LPS) of the Pseudomonas fluorescens strain IMV 7769 (biovar I) was isolated and investigated. Fractions of the structural parts of the LPS macromolecule, lipid A, the core oligosaccharide, and the O-specific polysaccharide (O-PS), were obtained in a homogeneous state. 2-Hydroxydecanoic, 3-hydroxydecanoic, dodecanoic, 2-hydroxydodecanoic, 3-hydroxydodecanoic, hexadecanoic, octadecanoic, hexadecenoic, and octadecenoic fatty acids were identified in lipid A. In the hydrophilic moiety of lipid A, after acid hydrolysis, several amino acids, phosphoethanolamine, glucosamine, and three unidentified peaks forming a separate cluster together with glucosamine were found. Lipid A was shown to be phosphorylated. Glucose, fucose, rhamnose, glucosamine, galactosamine, two unidentified amino sugars, 2-keto-3-deoxyoctulonic acid (KDO), heptose, ethanolamine, phosphoethanolamine, and alanine were identified in the core oligosaccharide. O-PS of the LPS consisted of repeating trisaccharide fragments that included residues of amino sugars: 4-acetamido-4,6-dideoxy-D-galactose, 2-acetamido-2,6-dideoxy-D-glucose, and 2-acetamido-2,6-dideoxy-L-glucose. During growth, the strain under study excreted exocellular LPS (ELPS) into the medium. The LPS studied was similar to the LPS of the earlier investigated strains P. fluorescens (biovar I) IMV 1152 and IMV 1433 in the structure of O-PS, but differed from them in the composition of both lipid A and the core oligosaccharide. The LPS of the strain studied differed from LPS of the type strain P. fluorescens IMV 4125 (ATCC 13525) in all characteristics determined.

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-->.

Structure of the O polysaccharide and immunochemical relationships between the lipopolysaccharides of Pseudomonas syringae pathovar tomato and pathovar maculicola.

O polysaccharides (OPS) of the lipopolysaccharides (LPS) of Pseudomonas syringae pathovar tomato GSPB 483 and pathovar maculicola IMV 381 were studied by 1H-NMR and 13C-NMR spectroscopy, including two-dimensional COSY, rotating-frame NOE spectroscopy (ROESY), and H-detected 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments. The OPS from both strains were shown to be chemically identical. Two structurally different types of repeating units (O repeats 1 and 2) were elucidated in each OPS. The minor O repeat is a pentasaccharide having the structure 2. The same structure has been reported earlier for some other OPS of P. syringae. The major O repeat is a hexasaccharide with the novel structure 1 which is distinguished from 2 by the presence of the second lateral residue of 3-acetamido-3,6-dideoxy-D-galactose (D-Fuc3NAc) and by a different position of substitution of one of the L-rhamnose (Rha) residues in the backbone. [structures: see text] Structural and serological diversity of OPS of strains belonging to P. syringae pv. tomato and pv. maculicola and phylogenetic relatedness of the strains are discussed.

Characterization of O-antigens from different strains of Pseudomonas syringae pv. tabaci.

O-Antigens (lipopolysaccharides, LPS) were isolated by NaCl extraction from microbial biomass of Pseudomonas syringae pv. tabaci and purified by ultracentrifugation. Individual structural components of the LPS macromolecule (O-specific polysaccharide (O-PS), core oligosaccharide, and lipid A) were obtained and characterized. Fatty acids 3-OH-C10:0, C12:0, 2-OH-C12:0, 3-OH-C12:0, C16:1, C16:0, C18:1, and C18:0 were identified in the lipid A composition. Glucosamine, ethanolamine, and phosphoethanolamine were found in the hydrophilic part of the lipid A macromolecule in all strains tested. Lipid A preparations contained phosphorus and amino acids. Rhamnose, glucose, glucosamine, 2-keto-3-deoxyoctulosonic acid, heptose, alanine, and phosphorus were identified as the main core components. The strains differed in O-PS structure. We describe the O-chain of LPS in strain P-28. It contains repeating units of the following structure: [formula: see text] The O-PS structures of LPS from strains P-28 and 225 are identical, however, they differ substantially from that of strain 223. Both structures from strains 223 and 225 were reported previously. Antibodies to antigenic epitopes of O-PS, core, and lipid A were revealed in O-serum against the whole bacterial cells. Correlation of O-PS structure with the serological grouping of strains was observed.

[Characterization of the lipopolysaccharide from the Pseudomonas fluorescens strain IMV 472 (biovar I)]. / Kharakteristika lipopolisakharida Pseudomonas fluorescens IMV 472 (biovar I).

Lipopolysaccharide was isolated from dry biomass of the Pseudomonas fluorescens strain IMV 472 (biovar I) by the Westphal procedure and purified by ultracentrifugation. Fractions of the structural components of the lipopolysaccharide macromolecule-lipid A, the core oligosaccharide, and the O-chain-were isolated and characterized. 3-Hydroxydecanoic, 2-hydroxydodecanoic, 3-hydroxydodecanoic, hexadecenoic, octadecenoic, and hexadecanoic acids were identified as the main fatty acids of lipid A. The hydrophilic moiety of lipid A was found to include glucosamine, phosphoethanolamine, and phosphate. Glucose, galactose, rhamnose, glucosamine, galactosamine, alanine, phosphoethanolamine, and 2-keto-3-deoxyoctulosonic were identified in the core region of lipid A. The O-specific polysaccharide chain consisted of a repeating tetrasaccharide fragment that included two L-rhamnose residues, a D-fucose residue, and an N-acetyl-D-glucosamine residue as a side substituent. Double immunodiffusion in agar and the lipopolysaccharide precipitation reaction revealed no serological interrelation between strain IMV 472 and P. fluorescens strains studied previously.