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Biochemical studies on the cell wall lipopolysaccharides (O-antigens) of Vibrio cholerae 569 B (Inaba) and El-tor (Inaba).

Lipopolysaccharides were isolated from the cell walls of Vibrio cholerae 569 B (Inaba) and El-tor (Inaba). Chemical analysis revealed the presence of glucose, fructose, mannose, heptose, rhamnose, ethanolamine, fatty acids and glucosamine. The lipopolysaccharides do not contain 2-keto-3-deoxyoctonate, the typical linking sugar of polysaccharide and lipid moieties of enterobacterial lipopolysaccharides. Galactose, a typical core polysaccharide component of many gram-negative bacteria was also absent from lipopolysaccharides of these organisms. By hydrolysis in 1% acetic acid, the lipopolysaccharides have been separated into a polysaccharide part (degraded polysaccharide) and a lipid part (lipid A). Components of degraded polysaccharide and lipid A moiety were identified and determined. The lipid A fractions contained fatty acids, phosphorus and glucosamine. All the neutral sugars detected in lipopolysaccharides were shown to be the constituents of its polysaccharide moiety. The fatty acid analysis of lipopolysaccharide and lipid A showed the presence of both hydroxy and non hydroxy acids. They were different from those of lipids extracted from cell walls before the extraction of lipopolysaccharides. 3-Hydroxylauric and 3-hydroxymyristic acids predominated in lipopolysaccharide and lipid A of Vibrio cholerae and El-tor (Inaba).

Cell Wall↗

Structural studies of the antigenic polysaccharide of Eubacterium saburreum, strain T27.

The antigenic polysaccharide produced by Eubacterium saburreum, strain T27, is a homoglycan composed of D-glycero-D-galacto-heptose (Hep) residues having a nonasaccharide repeating-unit with the structure (leads to 6)-[alpha-Hepf-(1 leads to 4)]-beta-Hepp-(1) leads to (3)6)-[alpha-Hepf-(1 leads to 2), alpha-Hepf-(1 leads to 4)]-beta-Hepp-(1 leads to. The polysaccharide contains acetyl groups linked to O-2 (except to the 2,4,6-linked heptopyranosyl residue), O-3 and O-7 of part of both heptopyranosyl and heptofuranosyl residues. The assignment of an acetyl group at O-3 of part of the terminal heptofuranosyl and 4,6-linked heptopyranosyl groups is tentative.

Antigens, Bacterial↗

The effect of formalin-killing of Pasteurella multocida on the antigenicity and extractability of its lipopolysaccharide.

The extraction of lipopolysaccharides (LPS) from formalin-killed (FK) Pasteurella multocida strain X-73 and from cells not exposed to formalin (NF) were compared by the Westphal and phenol-chloroform-petroleum ether (PCP) extraction procedures. The LPS was determined by: (1) serologic analyses with antiserum specific for LPS; (2) analyses for toxicity; and (3) chemical analyses for components expected to be in LPS (such as hexoses, heptoses, amino sugars, 3-deoxyoctulosonic acid, and fatty acids). Strain X-73, the strain most virulent for chickens, was markedly affected by formalin killing. Unlike many strains, which readily yield LPS into the aqueous phase when extracted with phenol at 68 degrees by the Westphal procedure, strain X-73 did so only with FK and not with NF cells. With the NF cells, LPS was extracted by EDTA from the precipitate obtained during the Westphal procedure. With the PCP procedure, LPS was extracted readily from NF cells, but not from FK cells. The change in extractability of LPS as a result of formalin-killing was the same for both the encapsulated form of X-73 and a nonencapsulated variant derived from it. Although formalin-killing affected the extractability of LPS, no antigenic differences could be detected by immunodiffusion. However, the chick-embryo toxicity of LPS extracted from NF cells was greater than that of LPS from FK cells.

Animals↗

Structural studies of the O-antigen from Vibrio cholerae O:21.

The O-antigen from Vibrio cholerae O:21 has been investigated, using n.m.r. spectroscopy, methylation analysis, and Smith degradation as the main methods. It is concluded that the O-antigen is composed of tetrasaccharide repeating-units having the following structure (in which Hep = D-glycero-D-manno-heptose). (Formula: see text).

Antigens, Bacterial↗

Lipopolysaccharides of Proteus penneri species novum.

The lipopolysaccharides (LPS), obtained from twenty strains of Proteus penneri, were shown to contain 3-deoxy-D-manno-2-octulosonic acid (KDO), L-glycero-D-manno- and D-glycero-D-manno-heptoses, glucose, 2-amino-2-deoxyglucose, 2-amino-2-deoxygalactose, and galacturonic acid. Galactose was lacking in three LPS and, in some LPS, glucuronic acid, rhamnose, lysine, and two unknown constituents were detected. Chemotypes of the P. penneri are discussed.

Amino Acids↗

Structural studies of the Vibrio cholerae O:3 O-antigen polysaccharide.

The structure of the Vibrio cholerae O:3 O-antigen polysaccharide has been investigated, mainly by n.m.r. spectroscopy, mass spectrometry, sugar and methylation analysis, and specific degradations, and is proposed to involve the following tetrasaccharide repeating-unit. [formula: see text]. In this structure, D-D-Hep is D-glycero-D-manno-heptose, Asc is 3,6-dideoxy-L-arabino-hexose (ascarylose), and Sug is 2,4-diamino-2,4,6-trideoxy-D-glucose (bacillosamine) in which N-2 is acetylated and N-4 is acylated with a 3,5-dihydroxyhexanoic acid. That the 2,4-diamino-2,4,6-trideoxy-D-glucose residue is linked through O-3 and not through one of the hydroxyl groups in the 3,5-dihydroxyhexanoyl group is indicated but not definitely proved. The configuration of the latter group has not been determined. The f.a.b.-mass spectrum of the methylated O-antigen indicates that the structure given above also represents the biological repeating-unit.

Carbohydrate Conformation↗

Taxonomic implication of the apparent undetectability of 3-deoxy-D-manno-2-octulosonate (Kdo) in lipopolysaccharides of the representatives of the family Vibrionaceae and the occurrence of Kdo 4-phosphate in their inner-core regions.

After conventional hydrolysis of lipopolysaccharides (LPSs), Kdo was not detectable by the periodate-thiobarbituric acid test in those of any member of Vibrionaceae except the gems Plesiomonas, but phosphorylated Kdo was demonstrated after strong-acid hydrolysis. Dephosphorylation, periodate oxidation, and methylation analysis of LPS preparations from 7 strains selected from all genera of Vibrionaceae, except Plesiomonas, showed that the inner-core region (unlike that in enteric Gram-negative bacteria) contains only one molecule of Kdo 4-phosphate 5-substituted with heptose, a constituent of the distal part of the core region, as in enteric bacteria. The undetectability of Kdo in LPS after conventional hydrolysis and the occurrence of phosphorylated Kdo in strong-acid hydrolysates and of Kdo 4-phosphate in the inner-core region are taxonomic characteristics of the family Vibrionaceae.

Hydrolysis↗

Characterization of structural defects in the lipopolysaccharides of symbiotically impaired Rhizobium leguminosarum biovar viciae VF-39 mutants.

The lipopolysaccharides (LPS) of a wild type strain of Rhizobium leguminosarum biovar viciae (strain VF-39) and two symbiotically defective Tn5 mutants (VF-39-32 and VF-39-86) have been studied. The LPS of the mutants reflected impaired synthesis of the O-antigen. In the LPS of one mutant, the core tetrasaccharide was lacking and in that of the other it was truncated to a disaccharide containing mannose and 3-deoxy-D-manno-oct-2-ulosonic acid (KdO). The latter mutant also synthesized an unusual carbohydrate component containing mannose, galactose, and an unidentified saccharide. The lipid A composition was similar to that found in other strains of R. leguminosarum biovar viciae. The O-antigen of the wild-type bacterium contained 2-O-methylfucose, fucose, 3,6-dideoxy-3-(methylamino)hexose, glucose, 2-amino-2,6-dideoxyhexose, and heptose. This study clearly defines a role for the bacterial LPS in the proper functioning of the Rhizobium legume symbiosis.

Carbohydrate Conformation↗

Structural studies of the antigenic polysaccharide of Eubacterium saburreum, strain T19.

The antigenic polysaccharide produced by Eubacterium saburreum, strain T19, contains unusual sugars, including D-glycero-D-galacto-heptose (Hep) and D-fucose (D-Fuc). A repeating unit of the polysaccharide is composed of a linear chain of D-glycero-D-galacto-heptopyranosyl tetrasaccharide as its backbone structure, i.e., -[-->6)-beta-Hep p-(1-->3)-beta-Hep p-(1-]2-->, and a D-fucofuranosyl disaccharide as a branched group, i.e., alpha-D-Fuc f-(1-->2)-alpha-D-Fuc f-(1-->, which is linked to O-4 of one (1--6)-linked D-glycero-D-galacto-heptopyranosyl residue. The polysaccharide also contains O-acetyl groups.

Carbohydrate Conformation↗

Structural studies of the saccharide part of the cell envelope lipooligosaccharide from Haemophilus influenzae strain galEgalK.

The structure of the saccharide part of the lipooligosaccharide from Haemophilus influenzae strain galEgalK has been investigated. On treatment of the lipooligosaccharide with acid under mild conditions, followed by reduction with sodium borohydride and gel permeation chromatography, a main fraction was obtained which was studied by methylation analysis, NMR spectroscopy, and FABMS. The material was heterogeneous and contained two major compounds, A and B, and one minor, C. [formula: see text] In the structure, PEA is phosphoethanolamine, and L-D-Hep is L-glycero-D-manno-heptose. Kdo exists in reduced anhydro forms. The carbohydrate backbone is the same as that proposed for the saccharide part of the major component from H. influenzae type b strain A2 [N.J. Phillips, M. A. Apicella, J. M. Griffiss, and B. W. Gibson, Biochemistry, 32 (1993) 2003-2012].

Antigens, Bacterial↗

Structures of decasaccharide and tridecasaccharide tetraphosphates isolated by strong alkaline degradation of O-deacylated lipopolysaccharide of Pseudomonas fluorescens strain ATCC 49271.

Mild hydrazinolysis of Pseudomonas fluorescens strain ATCC 49271 lipopolysaccharide (LPS) followed by strong alkaline degradation and purification by anion-exchange HPLC resulted in two phosphorylated oligosaccharides (1 and 2). On the basis of compositional analysis and 1H, 13C, and 31P NMR spectroscopy, including 2D correlation spectroscopy (COSY), 2D rotating frame NOE spectroscopy (ROESY), and 2D inverse mode H-detected heteronuclear 1H-13C and 1H-31P correlation spectroscopy, the following two structures (1 and 2) could be identified [formula: see text] where Hep is L-glycero-D-manno-heptose, Kdo is 3-deoxy-D-manno-octulosonic acid, Non is 5,7-diamino-3,5,7,9-tetradeoxy-D-glycero-L-galacto-nonulosonic acid, and P is phosphate. Decasaccharide 1 and tridecasaccharide 2 represent an incomplete core and the complete core carrying one O-antigen repeating unit, respectively. Both are attached to the lipid A backbone but, due to their degradation protocol, they lack N- and O-acyl substituents, including N- and O-acetyl groups, the 5-N-acetimidoyl group of Non, the 2-N-alanyl group of GalN, and the 7-O-carbamoyl group of Hep as well as diphosphate, triphosphate, and, probably, some of the monophosphate groups that are present in the intact core oligosaccharide.

Alkalies↗

Structure of a decasaccharide isolated by mild acid degradation and dephosphorylation of the lipopolysaccharide of Pseudomonas fluorescens strain ATCC 49271.

Mild acid degradation of the Pseudomonas fluorescens strain ATCC 49271 lipopolysaccharide resulted in a core oligosaccharide containing D-glucose, 2-acetamido-2-deoxy-D- glucose, 2-(L- alanylamino)-2-deoxy-D-galactose, 2-acetamido-2,6-dideoxy-D-glucose (QuiNAc), 2-acetamido- 2,6-dideoxy-L-galactose (FucNAc), L-glycero-D-manno-heptose (Hep), 3-deoxy-D- manno-octulosonic acid (Kdo, present in multiple forms), and 5-acetamidino-7-acetamido-3,5,7,9- tetradeoxy- L-glycero-D-galacto-nonulosonic acid (a di-N-acyl derivative of legionaminic acid, Non) as well as O-acetyl, O-carbamoyl, and phosphate groups, including triphosphate groups. The dephosphorylated (HF) decasaccharide and products of its partial and full O-deacylation were studied by methylation analysis, GLC-MS, and 1H NMR spectroscopy, including 1D NOE and 2D shift-correlated spectroscopy (COSY). The core oligosaccharide of P. fluorescens strain ATCC 49271 was found to be a decasaccharide (with partially degraded Kdo region) and one O-antigen repeating unit (di-N-acyllegionaminic acid, Non) attached. The following structure of the dephosphorylated core oligosaccharide was established: [sequence: see text]

Acids↗

Structural analysis of the lipopolysaccharide from Vibrio cholerae O139.

The lipopolysaccharide (LPS) from Vibrio cholerae O139 was deacylated with KOH. The following structure of the oligosaccharide resulting from this treatment was established on the basis of monosaccharide and methylation analyses, 1H, 13C and 31P 1D and 2D NMR experiments and 1D analogues of 3D NOESY-TOCSY and 3D TOCSY-NOESY experiments. [formula: see text] 'C' is a beta-L-threo-hex-4-enuronopyranosyl residue. Hep is L-glycero-D-manno-heptose, QuiN is 2-amino-2,6-dideoxy-D-glucose, GlcN is 2-amino-2-deoxy-D-glucose, Glc is D-glucose, Fru is D-fructose, and Kdo is 3-deoxy-D-manno-2-octulosonic acid. All sugars are pyranoses except fructose which is furanosidic. The fructose residue was localised after deacylation of the LPS with anhydrous hydrazine, methylation, acid methanolysis, and remethylation using deuterated iodomethane. The elucidation of this structure allowed for a direct comparison to the previously determined structure for Vibrio cholerae O1 lipid A-core region. The two structures are almost identical, and, therefore, this study is consistent with the genetic data for the biogenesis of strain O139 from O1. Furthermore, the identification of a structural analogue to the capsular polysaccharide of O139 in the outer core of the LPS in conjunction with the identification of colitose as a constituent of the LPS, provides additional evidence that the O-antigen and capsular polysaccharide of this strain may share the same repeat unit.

Carbohydrate Conformation↗

The effect of bacterial lipopolysaccharide (LPS) on histamine release from human basophils. I. Enhancement of immunologic release by LPS.

Preincubation of human basophils with bacterial lipopolysaccharide (LPS) purified from the heptose-deficient mutant Salmonella minnesota R595 enhanced by an average of sixfold the response of peripheral blood basophils obtained from allergic donors to several allergens in vitro as judged by release of histamine. Enhancement occurred at suboptimal, optimal, and supraoptimal concentrations of antigen. No effect was seen if basophils were from a nonallergic donor, and LPS by itself rarely caused histamine release from any preparation of basophils. However, histamine release in basophils from nonallergic donors induced by antibody directed against IgE (anti-IgE) also was enhanced by LPS. Potentiation of histamine release occurred if basophils were pretreated with LPS before addition of anti-IgE for as little as 5 min; there was no increase in release if anti-IgE and LPS were added simultaneously to cells. LPS enhanced the rate of release without altering duration of the release response. LPS potentiation of release of histamine by F(ab')2 fragments of anti-IgE was equivalent to its effect on release triggered by the intact antibody molecule, confirming that the effect of LPS is not due solely to its interaction with the Fc component of the anti-IgE. These data thus provide evidence for modulation of basophil response to IgE-mediated stimuli by LPS, resulting in a significant enhancement of response. Enhancement by LPS appears to be independent of the stimulus which triggers the IgE receptor. The contribution of this mechanism to allergic disease or asthma remains to be determined.

Adjuvants, Immunologic↗

Analysis of the 2-keto-3-deoxyoctonate (KDO) region of lipopolysaccharides isolated from non-01 Vibrio cholerae 05R.

Phosphorylated 2-keto-3-deoxyoctonate (KDO) has been detected in the strong-acid hydrolysates of lipopolysaccharides (LPS) of family Vibrionaceae including Vibrio cholerae. Structural analysis of LPS isolated from a rough mutant of non-01 V. cholerae 05 by dephosphorylation, periodate oxidation and methylation analysis revealed that the inner core region of the LPS molecule contains only one mole of KDO in contrast to enteric Gram-negative bacterial LPS, and that the phosphate group on the KDO molecule resides in the C4 position, while the site of binding of KDO to heptose, a constituent of the distal part of the inner core region, is the C5 position as in the enteric bacterial LPS.

Chromatography, Gas↗

Comparative study of lipopolysaccharides from Wolinella recta, W. curva, W. succinogenes and Campylobacter sputorum ssp. sputorum.

Lipopolysaccharides (LPS) were extracted from cells of Wolinella recta ATCC 33238, W. curva ATCC 33224, W. succinogenes ATCC 29543 and Campylobacter sputorum ssp. sputorum A 3563 by a hot phenol-water method and purified by nuclease treatment and by repeated ultracentrifugation. Chemical compositions of the purified LPS including fatty acid and sugar composition were examined and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed. All LPS preparations contained a monosaccharide identified as L-glycero-D-mannoheptose, and another heptose isomer identified as D-glycero-D-mannoheptose was a typical constituent of the LPS from all three Wolinella species.

Campylobacter↗

Extraction and characterization of lipopolysaccharide from Pseudomonas pseudomallei.

The best yield of lipopolysaccharide (LPS) of Pseudomonas pseudomallei GIFU 12046 was obtained by extraction of defatted cells by phenol/chloroform/petroleum ether. The LPS showed a smooth character on SDS-polyacrylamide gel electrophoresis and contained D-glucose, L-glycero-D-manno-heptose, and D-glucosamine as the main sugar components, and 3-hydroxypalmitic acid as an amide-linked fatty acid. The growth conditions did not affect the electrophoresis profile and chemical composition of LPS. 2-Keto-3-deoxyoctonic acid was not detectable, and mild acid hydrolysis could not liberate free lipid A, suggesting that the linkage between inner core and lipid A was stable against acid hydrolysis, and the structure of this region is similar to that of P. cepacia, which has close taxonomic relationship with P. pseudomallei.

Burkholderia pseudomallei↗

Chemical composition of lipopolysaccharide from Moraxella bovis.

Lipopolysaccharide from Moraxella bovis was isolated and its components characterized by paper and gas-liquid chromatography and mass spectrometry. The endotoxin showed a small amount of protein and contained 2-keto-3-deoxyoctonic acid glucose, mannose, glucosamine, heptose and phosphate. Six fatty acids (palmitic, palmitoleic, margaric, stearic, oleic and arachidic acids) were also identified. Margaric acid was the most prevalent fatty acid present in the lipid fraction.

Animals↗