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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Brucella endotoxin differs from other gramnegative endotoxins in that it is recovered in the phenol phase rather than the aqueous phase of the Westphal hot phenol water procedure. This was the first described from this laboratory by Redfearn (1960) with phenol-killed smooth B. abortus and B. melitensis and has since been confirmed by others. Preliminary extraction of brucella cells with acetone, as called for in the original Westphal procedure, was followed by Renoux et al. (1973) who reported that the aqueous phase lacked endotoxic activity and the phenol phase had very low toxicity. In order to test the hypothesis that prior acetone extraction removes lipid A, we have repeated the Redfearn procedure with acetone extracted cells and have confirmed that the major portion of the endotoxic activity resides in the phenol phase. Acetone treatment does not remove the lipid A believed to be responsible for mouse lethality as well as necrotizing activity in guinea pig and rabbit skin. Preparations of brucella endotoxin (lipopolysaccharide) contain varying amounts of polypeptide some of which is tightly bound. The dermal response of sensitized guinea pigs to brucella LPS was shown to be a combination of reactions comprising those due to (1) innate toxicity of lipid A, (2) antibody mediated reactions due to polysaccharide portion of the molecule and (3) delayed hypersensitivity due to polypeptide portion of the molecule.
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PMID:Studies of Brucella lipopolysaccharide. 126 51

The analysis of the components of a bacterium may be envisaged from the biological aspect (fractionation), the ultrastructural aspect (staining of the structures examined electron-microscopically), and the biological aspect (measure of an activity). In this report we attempt to examine the components of brucella from all three aspects simultaneously. The brucella envelopes have the same ultrastructure as that of gramnegative bacteria: outer membrane, thick stratum or peptidoglycane, periplasmic space, cytoplasmic membrane. The outer membrane of brucella in phase S contains many types of polysaccharides: (1) the lipopolysaccharide (LPS) (S) and polysaccharide B are solubilized by the phenol-uater and ether-water methods, by trichloracetic acid (TCA), by heated sodium dodecyl-sulfate (SDS). The exact localization of polysaccharide B is not known; by the phenol-water extraction method, the LPS (S) in its toxic form (endotoxin) passes in solution into the phenol phase, unlike the endotoxin of enterobacteria, which passes into the aqueous phase. In addition to its toxicity, this LPS (S) is responsible for reactions of immediate hypersensitivity as well as serological reactions towards the standard antigen. It presents A + M antigenic sites; (2) one or more of the polysaccharides remains unsolubilized by the ether-water method, but solubilized by heated SDS; (3) a polysaccharide is linked to peptidoglycane. The structure of the outer membrane of the brucella in phase R is analogous to that of LPS, carrying antigen R, characteristic of these strains. This antigen may be utilized for the serological diagnosis of infections due to brucella R (B. ovis) or vaccinations by a vaccine in phase R. The peptidoglycane fraction extracted by the heated SDS has a more complex structure than that of E. coli: it consists of a supplementary outer layer containing amino acids and polysaccharides. This fraction has a vaccinal activity. A soluble protein fraction, without organized structure, no doubt of cytoplasmic origin, may be extracted by a cold saline solution. This fraction, known as "brucelline", reveals delayed hypersensitivity when injected intradermally. The biological activity of the other structures (periplasm, cytoplasmic membrane, ribosomes...) is not known. Biological activities have been attributed to fractions, but since these are badly defined from the structural point of view it is difficult to determine the connection between activities and structures.
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PMID:[Structure and constituents of Brucella. Characterization and biological properties of the fractions]. 126 52

An investigation of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles of lipopolysaccharides (LPSs) extracted from seven strains of Helicobacter pylori revealed that these molecules were silver stainable and exhibited a high degree of variability in their patterns. Two strains synthesized a variety of sizes of LPS molecules such that fractionation by SDS-PAGE resulted in a stepwise gradation of bands which extended from the top to the bottom of the silver-stained gel. The LPSs from the remaining five strains were made up of molecules which were more homogeneous in size and clustered around two separate areas of the gel. Antigenic analyses of phenol-water-extracted LPSs by immunoblotting and the passive hemagglutination assay suggested that, in addition to strain-specific antigens, all of the LPSs carried a common antigen. Antibodies to this common antigen could be removed from antisera by absorption, and the resulting antisera were used to differentiate strains on the basis of their O antigens by the passive hemagglutination assay technique. The finding that LPSs from 3 of 10 clinical isolates reacted specifically in one or two of the typing antisera suggested that the development of a scheme for differentiating H. pylori on the basis of O antigens is feasible.
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PMID:Antigenicity of Helicobacter pylori lipopolysaccharides. 128 Jun 51

A transposon Tn5-induced mutant of Rhizobium meliloti Rm2011, designated Rm6963, showed a rough colony morphology on rich and minimal media and an altered lipopolysaccharide (LPS). Major differences from the wild-type LPS were observed in (i) hexose and 2-keto-3-deoxyoctonate elution profiles of crude phenol extracts chromatographed in Sepharose CL-4B, (ii) silver-stained sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis patterns of crude and purified LPS fractions, and (iii) immunoreactivities otherwise present in purified LPS of the parental strain Rm2011. In addition, Rm6963 lost the ability to grow in Luria-Bertani medium containing the hydrophobic compounds sodium deoxycholate or SDS and showed a decrease in survival in TY medium supplemented with high calcium concentrations. The mutant also had altered symbiotic properties. Rm6963 formed nodules that fixed nitrogen but showed a delayed or even reduced ability to nodulate the primary root of alfalfa without showing changes in the position of nodule distribution profiles along the roots. Furthermore, 2 to 3 weeks after inoculation, plants nodulated by Rm6963 were smaller than control plants inoculated with wild-type bacteria in correlation with a transient decrease in nitrogen fixation. In most experiments, the plants recovered later by expressing a full nitrogen-fixing phenotype and developing an abnormally high number of small nodules in lateral roots after 1 month. Rm6963 was also deficient in the ability to compete for nodulation. In coinoculation experiments with equal bacterial numbers of both mutant and wild-type rhizobia, only the parent was recovered from the uppermost root nodules. A strain ratio of approximately 100 to 1 favoring the mutant was necessary to obtain an equal ratio (1:1) of nodule occupancy. These results show that alterations in Rm6963 which include LPS changes lead to an altered symbiotic phenotype during the association with alfalfa that affects the timing of nodule emergence, the progress of nitrogen fixation, and the strain competitiveness for nodulation.
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PMID:A Rhizobium meliloti lipopolysaccharide mutant altered in competitiveness for nodulation of alfalfa. 132 69

1. Endotoxin-like activity was extracted with phenol-chloroform-petroleum either (PCP) from Leptospira interrogans serovars icterohaemorrhagiae and canicola. Chemical analysis of leptospiral cells obtained from the PCP extract indicated the following distribution of lipopolysaccharide (LPS), protein and polysaccharide in mg/ml: 3.0, 4.5 and 1.0 for icterohaemorrhagiae and 3.3, 5.6 and 1.5 for canicola. 2. The preparations presented several biological activities: positive Limulus test (1.0 pg/ml) for icterohaemorrhagiae and canicola PCP extract and 0.5 pg/ml for E. coli O111:B4 LPS, lethality for chicken embryos (LD50 45, 25 and 1.0) for icterohaemorrhagiae, canicola and E. coli O111:B4 LPS, pyrogenicity in rabbits with an average increase in rectal temperature of 0.6 degrees C, 0.9 degrees C and 2.2 degrees C for canicola, icterohaemorrhagiae and E. coli O111:B4 LPS, reacted with complement inhibiting the lysis of sheep red blood cells, 62%, 75% and 90% for 2.0 micrograms/ml of icterohaemorrhagiae, canicola PCP extract and E. coli O111:B4 LPS. The PCP extract showed no cytotoxicity on chicken embryo fibroblasts and epithelial cells. 3. These results demonstrate that Leptospira endotoxin activity is similar to E. coli O111:B4 lipopolysaccharide.
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PMID:Chemical and biological properties of endotoxin from Leptospira interrogans serovars canicola and icterohaemorrhagiae. 134 22

Two Salmonella hybrid strains, SL5313 (Salmonella typhimurium with a D.rfb+ gene cluster) and SL5396 (S. enteritidis with a B.rfb+ gene cluster), each expressing both O-antigen 4 (of serogroup B) and O-antigen 9 (of serogroup D) were studied by immunofluorescence using a mixture of O4-specific mouse monoclonal and O9-specific rabbit polyclonal antibodies. Bound antibodies, detected by anti-mouse antibody labelled with fluorescein isothiocyanate and anti-rabbit antibody labelled with tetramethylrhodamine isothiocyanate showed that more than 98% of the bacteria expressed both the O4 and O9 epitopes. Phenol-water-extracted lipopolysaccharide from batch-grown cultures subjected to sugar and methylation analyses by gas-liquid chromatography and mass spectrometry were shown to contain abequose (of the O4 epitope) and tyvelose (of the O9 epitope) in ratios of 1:1.5 and 1:2.5 for SL5313 and SL5396, respectively. Isolated polysaccharide chains, obtained by weak-acid hydrolysis of the lipopolysaccharides, were found to contain both O4 and O9 specificities in the same molecule, since polysaccharide bound to O4 antibody attached to a solid-phase-adsorbed O9-specific antibody and vice versa. This demonstrates that in strains SL5313 and SL5396 O chains containing both O4 repeating units (from S. typhimurium) and O9 units (from S. enteritidis) are present.
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PMID:Structural and immunochemical studies of the lipopolysaccharides of Salmonella strains with both antigen O4 and antigen O9. 137 17

Two structurally and immunologically different components of Bordetella pertussis endotoxin can be visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining: a major A band and a faster-migrating minor B band. Certain mutant strains of B. pertussis express only the B band, while the wild-type strains produce both lipooligosaccharides (LOS). Two monoclonal antibodies (MAbs) directed against the minor LOS B band were generated, allowing the study of this surface molecule on different strains of Bordetella. These two MAbs, designated BL-8 and BL-9, reacted strongly with phenol-water-purified LOS obtained from a B. pertussis LOS B mutant strain. Sodium periodate treatment of the purified LOS prevented binding of the MAbs, indicating the carbohydrate nature of the epitope(s). Western immunoblotting experiments revealed that the epitope(s) recognized by these MAbs is conserved on all B. pertussis and Bordetella bronchiseptica Vir- (avirulent) variant strains tested but is not present on Bordetella parapertussis and B. bronchiseptica Vir+ (virulent) wild-type strains. Further studies showed that although present in the lipopolysaccharide B band expressed by Vir- strains, the epitope(s) recognized by the MAbs is not accessible on the surface of intact B. bronchiseptica cells. For B. pertussis, the density and accessibility of this epitope(s) are dependent on the virulence-associated or LOS phenotype expressed by the strain. Our data demonstrate that the expression and accessibility of the epitope(s) are significantly greater on the LOS B variant strains and LOS AB Vir- strains compared with fresh B. pertussis clinical isolates. For these latter strains, which are Vir+, this epitope(s) was barely detectable on the surface of intact bacteria, despite Western blot analyses that revealed specific reactions between the MAbs and the LOS B band. The two LOS B-specific MAbs had no bacteriolytic activity against a LOS AB wild-type strain, while the control MAb BL-2, which is specific for the B. pertussis LOS A band, significantly reduced the number of living bacteria in the same assay. Moderate lytic activity against a mutant strain expressing only the LOS B band was observed for MAb BL-8 but not for MAb BL-9 or BL-2. These data demonstrate that the type, amount, and surface exposure of the LOS are related to the phenotype expressed by a specific B. pertussis strain. In addition, the LOS B MAbs also reveal the antigenic conservation of carbohydrate epitopes among B. pertussis and B. bronchiseptica strains.
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PMID:Immunological characterization of the lipooligosaccharide B band of Bordetella pertussis. 137 81

An ELISA was evaluated for the serodiagnosis of fowl typhoid and paratyphoid due to Salmonella enteritidis in chickens. The hot phenol: water lipopolysaccharide (LPS) extract of Salmonella was used as the antigen. Chicken serum, eggs and discs impregnated with chicken blood were tested for the presence of antibodies against Salmonella factor 'O' 9 antigen. The substrate and chromogen used were hydrogen peroxide and orthophenylenediamine respectively. Serological results from the experimentally and naturally infected chickens showed close agreement between the conventional Serum Tube Agglutination Test (SAT) and serum ELISA while serum ELISA results were in close agreement with the egg and disc ELISA results. It was noted that ELISA was highly sensitive, convenient and versatile. It is concluded that ELISA, especially disc ELISA, ought to replace SAT for seroscreening chickens against S. gallinarum and other Salmonella Group D infections.
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PMID:Serum, disc and egg ELISA for the serodiagnosis of Salmonella gallinarum and S. enteritidis infections in chickens. 138 Nov 7

Spleen cells from mice infected with the rough Brucella melitensis strain B115 were fused with NSO myeloma cells. Hybridoma supernatants were screened in ELISA with cell walls (CW), sonicated cell extracts (CE) and rough lipopolysaccharide (R-LPS) of B. melitensis strain B115 and whole B. melitensis B115 cells. Surprisingly, 22 monoclonal antibodies (mAbs) reacting in ELISA with both CW and CE but not with R-LPS and bacterial cells were shown by immunoblot analysis and ELISA to react with smooth lipopolysaccharide (S-LPS). These mAbs also reacted in ELISA with O polysaccharides (OPS) from the smooth Brucella abortus strain 99 and the smooth B. melitensis strain 16M and thus recognize epitopes present on the O-chain. Proteinase K LPS preparations from B. melitensis B115 analysed by immunoblotting with one mAb (12G12) recognizing S-LPS of both A and M specificity displayed the typical S-LPS high-molecular-mass ladder pattern but no S-LPS was detected in the phenol/water/chloroform/light petroleum LPS preparation of the same strain. mAb 12G12, specific for S-LPS, and a mAb (A68/03F03/D05) specific for R-LPS were used to localize the O-chain and R-LPS expressed in B. melitensis strain B115 by immunoelectron microscopy. Immunogold labelling was observed at the surface of B. melitensis B115 cells with the anti-R-LPS mAb but not with the anti-S-LPS mAb. In ultrathin sections, immunogold labelling with the S-LPS specific mAb was observed in the cytoplasm and in the periphery of the cytoplasm, probably at the cytoplasmic membrane.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:O-chain expression in the rough Brucella melitensis strain B115: induction of O-polysaccharide-specific monoclonal antibodies and intracellular localization demonstrated by immunoelectron microscopy. 138 11

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.
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PMID:Extraction and characterization of lipopolysaccharide from Pseudomonas pseudomallei. 138 80


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