Composition of O-antigenic lipopolysaccharides from Enterobacter cloacae

Analyses have been carried out on lipopolysaccharides (LPS) from 14 strains of Enterobacter cloacae representing different O serotypes. All of the products appeared to have a composition and architecture typical of enterobacterial LPS, but points of interest include the absence of phosphate residues from the core oligosaccharide, the presence of both L-glycero-D-mannoheptose and D-glycero-D-mannoheptose (ratio usually about 4:1), and the presence in lipid A of small amounts of fatty acids with odd numbers of carbon atoms (mainly C13) in addition to tetradecanoic acid and 3-hydroxytetradecanoic acid. Monosaccharides identified as components of polymeric fractions from the LPS were glucose, galactose, mannose, rhamnose, glucosamine, galactosamine, fucosamine, and galacturonic acid. Most polymeric fractions also probably contained an O-acetyl substituent. Closely similar chemotypes found for the polymeric fractions from the LPS of cross-reacting serotypes support the view that these fractions contain the O-antigenic determinants and represent the side chains of the LPS.     

Chemical and physical properties of lipopolysaccharide of Yersinia pestis

Lipopolysaccharide (LPS) prepared from Yersinia pestis 195/P contained d-glucose, d-glycero-d-mannoheptose, l-glycero-d-mannoheptose, glucosamine, 3-deoxyoctulosonic acid, lipid A, beta-hydroxymyristate, acetyl, phosphate, and protein. Traces of ethanolamine, mannose, and galactose were also detected. The lipid A moiety was composed of glucosamine substituted with phosphate, amide-linked beta-hydroxymyristate, and amide-bound acetate. The absence of significant amounts of additional fatty acids indicates a lipid A structure somewhat less complex than that of other gram-negative bacteria. The sugars identified are those generally found in the "core" region of LPS from the Enterobacteriaceae, with the exception of the d-glycero-d-mannoheptose. The molecular weight of the aggregated LPS was estimated to be 1.6 x 10(8).     

Investigation of lipopolysaccharides from Sinorhizobium meliloti SKHM1-188 and two of its mutants with decreased nodulation competitiveness

A comparative study of the lipopolysaccharides (LPS) isolated from Sinorhizobium meliloti SKHM 1-188 and two its LPS-mutants (Th29 and Ts22) with sharply decreased nodulation competitiveness was conducted. Polyacrylamide gel electrophoresis with sodium dodecyl sulfate revealed two forms of LPS in all the three strains: a higher molecular-weight LPS1, containing O-polysaccharide (O-PS), and a and lower molecular-weight LPS2 without O-PS. However, the LPS1 content in mutants was significantly smaller than in the parent strain. The LPS of the strains studied contained glucose, galactose, mannose, xylose, three nonidentified sugars--X1 (TGlc 0.53), X2 (TGlc 0.47), and X3 (TGlc 0.43), glucosamine, and ethanolamine, while the LPS of S. meliloti SKHM1-188 additionally contained galactosamine, glucuronic and galacturonic acids, and 2-keto-3-deoxyoctulosonic acid (KDO), as well as fatty acids, such as 3-OH C14:0, 3-OH C15:0, 3-OH C16:0, 3-OH C18:0, nonidentified hydroxy X (T3-OH C14:0 1.33), C18:0, and unsaturated C18:1 fatty acids. The LPS of both mutants were similar in the component composition but differed from the LPS of the parent strain by a lower X2, X3, and 3-OH C 14:0 content and a higher KDO, C18:0, and hydroxy X content. The LPS of all the strains were subjected to mild hydrolysis with 1% acetic acid and fractionated on a column with Sephadex G-25. The higher molecular weight fractions (2500-4000 Da) contained a set of sugars typical of intact LPS and, supposedly, corresponded to the LPS polysaccharide portion (PS1). In the lower molecular weight fractions (600-770 Da, PS2), glucose and uronic acids were the major components; galactose, mannose, and X1 were present in smaller amounts. The PS1/PS2 ratio for the two mutants was significantly lower than for strain SKHM1-188. The data obtained show that the amount of O-PS-containing molecules (LPS1) in the heterogeneous lipopolysaccharide complex of the mutants was smaller than in the SKHM1-188 LPS; this increases the hydrophobicity of the cell surface of the mutant bacteria. This supposedly contributes to their nonspecific adhesion on the roots of the host plant, thus decreasing their nodulation competitiveness.     

Biochemical and immunological comparison of lipopolysaccharides from Bordetella species

Lipopolysaccharides (LPS) isolated from Bordetella pertussis, B. parapertussis and B. bronchiseptica were analysed for their chemical composition, molecular heterogeneity and immunological properties. All the LPS preparations contained heptose, 3-deoxy-D-manno-2-octulosonic acid, glucosamine, uronic acid, phosphate and fatty acids. The fatty acids C14:0, C16:0 and beta OHC14:0 were common to all the LPS preparations. LPS from B. pertussis strains additionally contained isoC16:0, those from B. parapertussis contained isoC14:0 and isoC16:0, and those from B. bronchiseptica contained C16:1. By SDS-PAGE, LPS from B. pertussis had two bands of low molecular mass, and the LPS from B. parapertussis and B. bronchiseptica showed low molecular mass bands together with a ladder arrangement of high molecular mass bands. Immunodiffusion, quantitative agglutination and ELISA demonstrated that the LPS from B. pertussis strains reacted with antisera prepared against whole cells of B. pertussis and B. bronchiseptica; LPS from B. parapertussis reacted with antisera to B. parapertussis and B. bronchiseptica, and LPS from B. bronchiseptica reacted with anti-whole cell serum raised against any of the three species. From these results, it is concluded that LPS from B. bronchiseptica has structures in common with LPS from B. pertussis and B. parapertussis, while the LPS from B. pertussis and B. parapertussis are serologically entirely different from each other.     

Investigation of Lipopolysaccharides from Sinorhizobium meliloti SKHM1-188 and Two of Its Mutants with Decreased Nodulation Competitiveness

A comparative study of the lipopolysaccharides (LPS) isolated from Sinorhizobium meliloti SKHM1-188 and two of its LPS mutants (Tb29 and Ts22) with sharply decreased nodulation competitiveness was conducted. Polyacrylamide gel electrophoresis with sodium dodecyl sulfate revealed two forms of LPS in all three strains: a higher molecular weight LPS1, containing O-polysaccharide (O-PS), and a lower molecular weight LPS2, without O-PS. However, the LPS1 content in mutants was significantly smaller than in the parent strain. The LPS of the strains studied contained glucose, galactose, mannose, xylose, three nonidentified sugars (X ₁ (TGlc 0.53), X ₂ (TGlc 0.47), and X ₃ (TGlc 0.43)), glucosamine, and ethanolamine, while the LPS of S. meliloti SKHM1-188 additionally contained galactosamine, glucuronic and galacturonic acids, and 2-keto-3-deoxyoctulosonic acid (KDO), as well as such fatty acids as 3-OH C14:0, 3-OH C15:0, 3-OH C16:0, 3-OH C18:0, nonidentified hydroxy X (T_{3-OH C14:0} 1.33), C18:0, and unsaturated C18:1 fatty acids. The LPS of both mutants were similar in the component composition but differed from the LPS of the parent strain by lower X ₂, X ₃, and 3-OH C14:0 contents and higher KDO, C18:0, and hydroxy X contents. The LPS of all the strains were subjected to mild hydrolysis with 1% acetic acid and fractionated on a column with Sephadex G-25. The higher molecular weight fractions (2500–4000 Da) contained a set of sugars typical of intact LPS and, supposedly, corresponded to the LPS polysaccharide portion (PS1). In the lower molecular weight fractions (600–770 Da, PS2), glucose and uronic acids were the major components; galactose, mannose, and X ₁ were present in smaller amounts. The PS1/PS2 ratio for the two mutants was significantly lower than for strain SKHM1-188. The data obtained show that the amount of O-PS–containing molecules (LPS1) in the heterogeneous lipopolysaccharide complex of the mutants was smaller than in the SKHM1-188 LPS; this increases the hydrophobicity of the cell surface of the mutant bacteria, which supposedly contributes to their nonspecific adhesion to the roots of the host plant, thus decreasing their nodulation competitiveness.     

Chemical characterization of lipopolysaccharides from Proteus strains used in Weil-Felix test

The lipopolysaccharides (LPS) extracted from Proteus strains OX2, OX19, and OXK used as antigens in the Weil-Felix test, were characterized by chemical analysis and SDS-polyacrylamide gel electrophoresis (SDS-PAGE). To separate the O-polysaccharide, core-oligosaccharide, and lipid A moieties, each LPS was treated with 2% acetic acid, centrifuged, and applied to Sephadex G-50 column. The core-oligosaccharides contained L-glycero-D-mannoheptose, D-glycero-D-mannoheptose, glucose (Glc), galactose, 3-deoxy-D-mannooctulosonic acid, uronic acid, phosphate, glucosamine (GlcN), and galactosamine (GalN). The lipid A preparations contained GlcN, GlcN-phosphate, and three fatty acids (myristic, plamitic, and beta-hydroxymyristic acids). However, the O-polysaccharides of OX2- and OXK-LPS had different chemical compositions which consisted of Glc, GlcN, and quinovosamine, and Glc, uronic acid, and GalN, respectively, while OX19-LPS seemed to lack O-polysaccharide.     

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.     

Chemical and immunological characterization of lipopolysaccharides from phase I and phase II Coxiella burnetii.

Lipopolysaccharides (LPSs) isolated from phase I and phase II Coxiella burnetii (LPS I and LPS II, respectively) were analyzed for chemical compositions, molecular heterogeneity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunological properties. The yields of crude phenol-water extracts from phase I cells were roughly three to six times higher than those from phase II cells. Purification of LPSs by ultracentrifugation gave similar yields for both LPS I and LPS II. Purified LPS I and LPS II contained roughly 0.8 and 0.6% protein, respectively. The fatty acid constituents of the LPSs were different in composition and content, with branched-chain fatty acids representing about 15% of the total. beta-Hydroxymyristic acid was not detected in either LPS I or LPS II. A thiobarbituric acid-periodate-positive compound was evident in the LPSs; however, this component was not identified as 3-deoxy-D-mannooctulosonic acid by gas and paper chromatographies. LPS II contained D-mannose, D-glucose, D-glyceromannoheptose, glucosamine, ethanolamine, 3-deoxy-D-mannooctulosonic acid-like material, phosphate, and fatty acids. LPS I contained the unique disaccharide galactosaminuronyl glucosamine and nine unidentified components in addition to the components of LPS II. The hydrophobic, putative lipid A fraction of LPS I and LPS II contained the above constituents, but the hydrophilic fraction was devoid of ethanolamine. The LPS I disaccharide galactosaminuronyl glucosamine was found in both fractions of the acetic acid hydrolysates. Analysis of LPSs by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by silver staining indicated that LPS II was composed of only one band, whereas LPS I consisted of six or more bands with irregular spacing. Ouchterlony immunodiffusion tests demonstrated that LPS I reacted with phase I but not with phase II whole-cell hyperimmune antibody, and LPS II reacted neither with phase I nor phase II hyperimmune antibody. From these results, it was concluded that the chemical structures of LPSs from C. burnetii were different from those of the LPSs of gram-negative bacteria; however, the LPS structural variation in C. burnetii may be similar to the smooth-to-rough mutational variation of saccharide chain length in gram-negative bacteria.     

A Comparative Study of the Sugar Composition of O-antigenic Lipopolysaccharides Isolated from Vibrio alginolyticus and Vibrio parahaemolyticus

A comparative study of the sugar composition of O-antigenic lipopolysaccharides (LPS) isolated from Vibrio alginolyticus and those from V. parahaemolyticus was carried out. 3-Deoxy-d-mannooctulosonic acid, 2-keto-3-deoxy octonate (KDO), a regular sugar constituent of gram-negative bacterial LPS, was totally absent from LPS of all V. alginolyticus strains examined as it was from those of V. parahaemolyticus. Furthermore, a KDO-like thiobarbituric acid test-positive substance, identical with that of either V. parahaemolyticus 07 or 012, was also found in LPS from three strains, 505–78, 905–78, and 1013–79 (designated tentatively as group I), out of the five strains of V. alginolyticus tested. LPS from the members of group I contained, as component sugars, glucose, galactose, l-glycero-d-manno-heptose, glucosamine, galactosamine, the KDO-like substance, and an unidentified amino sugar P1. Thus, LPS of the members of group I possessed a similar sugar composition which is similar to that of LPS from either V. parahaemolyticus 07 or 012. LPS of strain 1027–79, one of the other two strains (designated tentatively as gorup II), contained as component sugars, glucose, l-glycero-d-mannoheptose, glucosamine, galactosamine, and the other unidentified amino sugar P2, while LPS of strain 53–79, the other member of group II, contained galactose as an additional component. The results indicate that LPS of strain 1027–79 has a sugar composition similar to that of V. parahaemolyticus 09 LPS.     

Cell surface polysaccharides from Bradyrhizobium japonicum and a nonnodulating mutant.

The cell surface polysaccharides of wild-type Bradyrhizobium japonicum USDA 110 and a nonnodulating mutant, strain HS123, were analyzed. The capsular polysaccharide (CPS) and exopolysaccharide (EPS) of the wild type and the mutant strain do not differ in their sugar composition. CPS and EPS are composed of mannose, 4-O-methylgalactose/galactose, glucose, and galacturonic acid in a ratio of 1:1:2:1, respectively. H nuclear magnetic resonance spectra of the EPS and CPS of the wild type and mutant strain are very similar, but not identical, suggesting minor structural variation in these polysaccharides. The lipopolysaccharides (LPS) of the above two strains were purified, and their compositions were determined. Gross differences in the chemical compositions of the two LPS were observed. Chemical and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses indicated that strain HS123 is a rough-type mutant lacking a complete LPS. The LPS of mutant strain HS123 is composed of mannose, glucose, glucosamine, 2-keto-3-deoxyoctulosonic acid, and lipid A. The wild-type LPS is composed of fucose, xylose, arabinose, mannose, glucose, fucosamine, quinovosamine, glucosamine, uronic acid, 2-keto-3-deoxyoctulosonic acid, and lipid A. Preliminary sugar analysis of lipid A from B. japonicum identified mannose, while traces of glucosamine were detected. 3-Hydroxydodecanoic and 3-hydroxytetradecanoic acids formed a major portion of the fatty acids in lipid A. Lesser quantities of nonhydroxylated 16:0, 18:0, 22:0, and 24:0 acids also were detected.     

Chemical characterization of effective and ineffective strains of Rhizobium leguminosarum bv. viciae

Chemical composition of lipopolysaccharide (LPS) isolated from an effective (97) and ineffective (87) strains of R. l. viciae has been determined. LPS preparations from the two strains contained: glucose, galactose, mannose, fucose, arabinose, heptose, glucosamine, galactosamine, quinovosamine, and 3-N-methyl-3,6-dideoxyhexose, as well as glucuronic, galacturonic and 3-deoxyoctulosonic acid. The following fatty acids were identified: 3-OH 14:0, 3-OH 15:0, 3-OH 16:0, 3-OH 18:0 and 27-OH 28:0. The ratio of 3-OH 14:0 to other major fatty acids in LPS 87 was higher that in LPS 97. SDS/PAGE profiles of LPS indicated that, in lipopolysaccharides, relative content of S form LPS I to that of lower molecular mass (LPS II) was much higher in the effective strain 97 than in 87. All types of polysaccharides exo-, capsular-, lipo, (EPS, CPS, LPS, respectively) examined possessed the ability to bind faba bean lectin. The degree of affinity of the host lectin to LPS 87 was half that to LPS 97. Fatty acids (FA) composition from bacteroids and peribacteroid membrane (PBM) was determined. Palmitic, stearic and hexadecenoic acids were common components found in both strains. There was a high content of unsaturated fatty acids in bacteroids as well as in PBM lipids. The unsaturation index in the PBM formed by strain 87 was lower than in the case of strain 97. Higher ratio of 16:0 to 18:1 fatty acids was characteristic for PMB of the ineffective strain.     

Heterogeneity and variation among Neisseria meningitidis lipopolysaccharides.

Eight immunotype lipopolysaccharides (LPSs) of Neisseria meningitidis were prepared by the phenol-water procedure and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and sugar analyses. By SDS-PAGE and a highly sensitive silver strain. N. meningitidis LPSs from cells grown in tryptic soy broth were shown to contain one or two predominant components and a few minor, somewhat higher-molecular-weight components. The molecular sizes of the two predominant components were approximately the same as those of two E. coli rough-type LPSs, one with a complete core and the other with an incomplete core. The molecular weight of the major LPS component varied somewhat among different immunotypes but was estimated to be in the range of 4,200 to 5,000. By sugar analyses, the eight immunotype LPSs were different in their monosaccharide compositions. All contained glucose, galactose, heptose, glucosamine, and 2-keto-3-deoxyoctonate, but in different molar ratios. The growth of N. meningitidis in tryptic soy broth under different levels of aeration resulted in a change in the two major LPS components seen on the SDS-PAGE gel. High aeration increased the amount of the smaller component, whereas low aeration increased the amount of the larger component. Sugar analyses of LPSs from high and low aeration indicated that the larger LPS component contained more galactose residues per molecule. Use of different media for cell growth may also result in small, but noticeable, variations in the LPS components and in the galactose content of the LPS. The observed heterogeneity of N. meningitidis LPS may explain why many strains of N. meningitidis appear to possess more than one immunotype.     

Isolation and characterisation of the lipopolysaccharide from Acidiphilium strain GS18h/ATCC55963, a soil isolate of Indian copper mine

The lipopolysaccharide (LPS) of the Gram-negative Acidiphilium strain GS18h/ATCC55963, a new soil isolate, exhibited very low endotoxic activity as determined by Limulus gelation activity, lethal toxicity in galactosamine (GalN) sensitised mice, and level of tumor necrosis factor alpha (TNFalpha) in the blood serum of BALB/c mice. Analysis of the LPS, specially of lipid A which usually accounts for the toxicity, revealed the latter to contain glucosamine and phosphate besides fatty acids, of which 14:0(3-OH), 18:0(3-OH), 18:1 and 19:0(cyclo) are the major components, while 12:0, 16:0, 19:1, 20:0(3-OH) and 20:1(3-OH) are present in small amounts. The 14:0(3-OH) and 18:0(3-OH) fatty acids are amide-linked, whereas the rest are ester bound. Glucose, galactose, mannose, rhamnose, heptose, galacturonic acid and 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) were present in the polysaccharide part of this LPS. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the LPS showed a macromolecular heterogeneity distinctly different from those of Escherichia coli or Salmonella. The toxicity of this LPS being extremely low attributed to fatty acid composition of its lipid A, promises potential therapeutic application.     

Lipopolysaccharides from six strains of Acetobacter diazotrophicus

Abstract Lipopolysaccharides from six nitrogen-fixing strains of Acetobacter diazotrophicus (PR2, PAL3, PAL5, PR4, PR14, PR20), isolated from sugarcane, were purified by phenol-water extraction and ultracentrifugation. The relatively large molecular mass observed by SDS-PAGE indicated that the lipopolysaccharides of each strain possessed an O-side chain. Analysis of each lipopolysaccharide by colorimetric assays and by gas liquid chromatography/mass spectrometry combination showed that the core and lipid A composition was similar for all strains, containing 3-deoxy-d-manno-2-octulosonic acid, glucosamine and fatty acid (16-0, 3-OH-14, 2-OH-16:0, 3-OH-16:0). The neutral sugar composition showed the predominance of 6-deoxy-hexose (rhamnose and fucose) and ribose, in comparison with hexose (glucose, galactose, mannose). The presence of 6-deoxy-hexose and ribose containing O-side chains is discussed as a way of discriminating A. diazotrophicus from other Acetobacter species.     

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.     

Chemical Analysis of Lipopolysaccharides of Shigella sonnei Form II Strains Expressed by Cloned Form I Antigen Genes

A compositional sugar analysis was carried out on lipopolysaccharide (LPS) from Shigella sonnei form II in which a plasmid with cloned form I antigen genes had been introduced. The recipient form II strains contained galactose, glucose, heptose, glucosamine, and 2-keto-3-deoxyoctonic acid (KDO) (2: 3: 1: 2: 2) in its LPS, while the transformant form I LPS contained, besides these sugars, N-acetyl-L -altrosaminouronic acid as an additional sugar constituent, which is known to be one of the antigenic determinants of form I antigen.     

Chemotypes of Veillonella lipopolysaccharides

Lipopolysaccharides (LPS) were isolated by phenol-water extraction from 34 strains of Veillonella, and examined by paper chromatography and colorimetric methods for the presence of neutral sugars, amino sugars and 2-keto-3-deoxy-octonate (KDO). Several preparations were also examined for neutral sugars by gas liquid chromatography. The LPS had in common glucosamine, galactosamine, L-glycero-D-manno-heptose glucose and KDO. Most LPS contained galactose, and a few rhamnose. D-glycero-D-manno-heptose was found in LPS from one of the strains. Based on the sugar composition of the LPS, the Veillonella strains could be classified into four chemotypes.     

The structure of the lipid A component of Sphaerotilus natans

The lipopolysaccharide of Sphaerotilus natans afforded a ladder-like pattern of bands in sodium deoxycholate-polyacrylamide gel electrophoresis, indicating the presence of a S-form lipopolysaccharide. The chemical analysis showed neutral sugars (rhamnose, glucose, l-glycero-d-manno-heptose), 3-deoxy-octulosonic acid (Kdo), amino compounds (glucosamine, glucosamine phosphate, ethanolamine and ethanolamine phosphate), and phosphorus. The lipid A fraction contained saturated and unsaturated capric, lauric, and myristic acids, and 3-hydroxy capric acid (3-OH-10:0). Its chemical structure was consisting of a glucosamine disaccharide, glycosidically substituted by a phosphomonoester, and substituted at C-4 by a pyrophosphodiester esterified with ethanolamine. The amino groups of both glucosamines are acylated by 3-hydroxy capric acids and these in turn are substituted by saturated and unsaturated capric, lauric, and myristic acids. Hydroxyl groups of the backbone disaccharide at C-3 and C-3 were also esterified by 3-hydroxy capric acid, those at C-4 and C-6 were unsubstituted. The latter provides the attachment site for Kdo.Abbreviations Kdo 3-deoxy-d-manno-octulosonic acid - 3-OH-10:0 3-hydroxy capric acid - DOC-PAGE deoxycholate-polyacrylamide gel electrophoresis - GC-MS gas chromatography/mass spectrometry - LD-MS laser desorption mass spectrometry - LPS lipopolysaccharide - PS polysaccharide     

Composition,structure, and biological properties of lipopolysaccharides from different strains of <Emphasis Type="Italic">Pseudomonas syringae</Emphasis> pv. <Emphasis Type="Italic">atrofaciens</Emphasis>

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-C_10:0, C_12:0, 2-HO-C_12:0, 3-HO-C_12:0, C_16:0, C_16:1, C_18:0, and C_18:1 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-mannooctonoic 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 substituent. 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.     

Structural analysis of the core region of the lipopolysaccharides from eight serotypes of Klebsiella pneumoniae

The core regions of the lipopolysaccharides (LPS) from Klebsiella pneumoniae serotypes O1, O2a, O2a,c, O3, O4, O5, O8, and O12 were analysed using NMR spectroscopy, ESI-MS spectroscopy, and chemical methods. All the LPSs had similar core structures, as shown below, differing only in the number and position of beta-D-galacturonic acid substituents: [carbohydrate structure: see text] where P is H or alpha-Hep, J, K is H or beta-GalA. LPS from all serotypes contained varying proportions of structures having additional or missing phosphate substituents. The core from serotype O1 contained a minor amount of a previously described variant with alpha-DD-Hep-(1-->2)-alpha-DD-Hep-(1-->6)-alpha-GlcN-(1--> replacing the alpha-Hep-(1-->4)-alpha-Kdo-(2-->6)-alpha-GlcN-(1--> component.