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

Two species of neutral glycosphingolipids purified from rat colon carcinoma tissue, isoglobotetraosylceramide [GalNAc(beta 1----3)Gal(alpha 1----3)Gal(beta 1----3)Glc(beta 1----1)Cer] and a related 6-sugar "analogue" were inserted into liposomes together with lipid A (from bacterial lipopolysaccharide) and used for immunization of mice and monoclonal antibody production. The yield of hybridomas producing glycolipid-specific antibody was 5-10% using a high-dose booster schedule with liposome-inserted glycolipid. In contrast the frequency was below 0.1% (no glycolipid-binding antibodies were found) when using the previously described method of immunizing with glycolipid coated on the surface of acid-treated S. minnesota. Monoclonal antibodies were screened on the purified glycolipids used for immunization and selected for differential reactivity to the two glycolipids. A diversity of specificities was demonstrated by binding to the purified antigens, in a thin-layer chromatogram binding assay and in binding tests to tumor and normal target cells.
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PMID:Production of oligosaccharide-binding monoclonal antibodies of diverse specificities by immunization with purified tumor-associated glycolipids inserted into liposomes with lipid A. 374 33

Glucan, a beta 1,3-linked polyglucose, is an effective macrophage activating and tumor-inhibitory agent. Previous studies indicate that glucan enhances macrophage-mediated tumoricidal activity. The present study was designed to examine the ability of glucan to enhance the production of tumor cell cytotoxic/cytostatic factor(s) designated, because of their macrophage origin, as macrophage cytotoxic factor(s) (MCF). Resting splenic macrophages in culture for 20 h secreted detectable levels of MCF. Coincubation of macrophages with bacterial endotoxin lipopolysaccharide (LPS) resulted in an enhancement of MCF production, compared to resting macrophages. Glucan-activated macrophages were more effective in producing MCF than both resting and LPS-activated macrophages. The MCF was cytotoxic to certain tumor cell lines at high concentrations and cytostatic at lower concentrations. The MCF was not significantly cytotoxic to N3T3 or BC/Sk murine fibroblasts, denoting specificity in response. Loss of MCF activity occurred following coincubation of macrophage culture supernatant with adenocarcinoma cells but not with normal fibroblasts. The MCF activity eluted at 38,000 and 84,000 daltons following column chromatographic analysis, and was heat labile at 100 degrees C but not 56 degrees C. In addition, MCF activity was diminished by protease inhibitors and antisera against tumor necrosis factor. Induction of MCF secretion may be an additional mechanism of glucan-induced antitumor activity.
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PMID:Glucan stimulates production of antitumor cytolytic/cytostatic factor(s) by macrophages. 379 56

The lysogenization of Pseudomonas aeruginosa PAO by phage D3 results in derivatives which are resistant to superinfection by phage D3c by virtue of the fact that homologous phage cannot adsorb to these cells. The serologically and morphologically unrelated phage E79 showed a markedly decreased adsorption rate to the lysogen PAO(D3). Since both of these phages are lipopolysaccharide specific, these results suggested lysogenic conversion of the phage receptor. The lipopolysaccharide was extracted from strain PAO by the hot phenol-water technique, but this procedure was ineffective with PAO(D3). We developed a technique involving cold trichloroacetic acid extraction, followed by ultracentrifugation, digestion of the high-speed pellet with proteinase K, and ultimate purification on CsCl step gradients. The lipopolysaccharide from the wild type had inactivating activity against D3 and E79, whereas that from PAO(D3) inactivated neither. Chromatographic analysis indicated that the convertant lipopolysaccharide was smooth, and quantitative chemical analyses of the two preparations showed no differences in the level of the major fatty acids, amino compounds, or neutral sugars. On the other hand, sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the side chains had a decreased migration rate through the gel matrix. The application of 1H and 13C nuclear magnetic resonance spectroscopic analysis revealed that the PAO side chain is chemically identical to that of serotype O:2a,d, containing 2,3-(1-acetyl-2-methyl-2-imidazolino-5,4)-2,3-dideoxy-D-mannuronic acid, 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid, and 2-acetamido-2,6-dideoxy-D-galactose (D-fucosamine). The molecular basis of the conversion event was (i) the introduction of an acetyl group into position 4 of the fucosamine residue and a change in the bonding between trisaccharide repeating units from alpha 1 leads to 4 to beta 1 leads to 4.
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PMID:O-antigen conversion in Pseudomonas aeruginosa PAO1 by bacteriophage D3. 619 Jul 94

The O-specific polysaccharide of the 0114 antigen (lipopolysaccharide) of Escherichia coli 0114 and oligosaccharides obtained from it by Smith degradation and hydrogen fluoride solvolysis were analyzed, using proton and 13C nuclear magnetic resonance spectroscopy and methylation. The results indicated that the 0114 polysaccharide has the tetrasaccharide repeating unit alpha-N-acetylglucosamine(1 leads to 4) beta-3,6-dideoxy-3-(N-acetyl-L-seryl)aminoglucose(1 leads to 3) beta-ribofuranose(1 leads to 4)galactose. In the polysaccharide the repeating units are joined through beta 1 leads to 3-galactosyl linkages. This structure is compared with that of the serologically cross-reacting Shigella boydii 08 antigen and the serological similarity is discussed.
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PMID:Cell-wall lipopolysaccharide of Escherichia coli 0114:H2. Structure of the polysaccharide chain. 630 15

The invertible G segment in phage Mu DNA controls the host range of the phage. Depending on the orientation of the G segment, two types of phage particles, G(+) and G(-), are produced which recognize different cell surface receptors. The receptor for Mu G(+) was located in the lipopolysaccharide (LPS) of gram-negative bacteria. The analysis of different LPS core types and of mutants that were made resistant to Mu G(+) shows that the primary receptor site on Escherichia coli K-12 lies in the GlcNAc beta 1 . . . 6Glc alpha 1-2Glc alpha 1-part at the outer end of the LPS. Mu shares this receptor site in E. coli K-12 with the unrelated single-stranded DNA phage St-1. Phage D108, which is related to Mu, and phages P1 and P7, which are unrelated to Mu but contain a homologous invertible DNA segment, have different receptor requirements. Since they also bind to terminal glucose in a different configuration, they adsorb to and infect E. coli K-12 strains with an incomplete LPS core.
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PMID:Cell wall receptor for bacteriophage Mu G(+). 638 94

Structural studies have been carried out on the O-specific fraction from the lipopolysaccharide of Pseudomonas aeruginosa NCTC 8505, Habs serotype 03. The O-specific polysaccharide has a tetrasaccharide repeating-unit containing residues of L-rhamnose (Rha), 2-acetamido-2-deoxy-D-glucose (GlcNAc), 2-acetamido-2-deoxy-L-galacturonic acid (GalNAcA), and 2,4-diacetamido-2,4,6-trideoxy-D-glucose (BacNAc2). The following structure has been assigned to the repeating-unit: leads to 3)Rhap(beta 1 leads to 6)GlcpNAc(alpha 1 leads to 4)GalpNAcA(alpha 1 leads to 3)BacpNAc2(alpha 1 leads to. The parent lipopolysaccharide is a mixture of S, R, and SR species, and its high phosphorus content is partly due to the presence of triphosphate residues, as found for other lipopolysaccharides from P. aeruginosa. In addition to phosphorus, heptose, a 3-deoxyoctulosonic acid, and amide-bound alanine, the core oligosaccharide contains glucose, rhamnose, and galactosamine (molar proportions 3:1:1). The rhamnose and part of the glucose are present as unsubstituted pyranoside residues: other glucose residues are 6-substituted.
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PMID:The lipopolysaccharide from Pseudomonas aeruginosa NCTC 8505. Structure of the O-specific polysaccharide. 640 10

A loosely bound lipopolysaccharide-protein complex was extracted from cells of Pseudomonas aeruginosa strain 170015 (O:7ab; Lanyi classification) by saline solution and purified from contaminant nucleic acid by Cetavlon treatment followed by precipitation in an ultracentrifuge. The saline-treated cells were re-extracted with hot aqueous phenol to give firmly bound lipopolysaccharide which was isolated from the phenol layer and purified by ultracentrifugaiton. The identity of both lipopolysaccharide preparations was proved by serological and chemical evidence. Mild acid degradation of the lipopolysaccharide resulted in the splitting off of a lipid component and led to polysaccharide which was purified by gel-filtration on a Sephadex G-50 column. The polysaccharide consisted of N-acetyl-D-fucosamine, N-acetyl-L-fucosamine and D-glucose in the ratio 1:1:1. On the basis of nuclear magnetic resonance spectra, results of methylation analysis and two sequential Smith degradations, the following structure can be assigned to the repeating unit of the polysaccharide: -3)LFucNAc(alpha 1-3)DFucNAc(beta 1-2)DGlc(beta 1-. The polysaccharide did not show serological activity whereas alkali-treated lipopolysaccharide readily sensitised sheep erythrocytes and inhibited the passive haemagglutination reaction with anti-(O:7a,b)serum. Evidence is presented that the oligosaccharide repeating units of the polysaccharide and alkali-treated lipopolysaccharide are indistinguishable. Ps. aeruginosa strain 170016 (O:7a,c) was shown to have the O-specific lipopolysaccharide identical with that from strain 170015. The presented data show that subfactors 7b and 7c in the Lanyi classification of Ps. aeruginosa O-antigens seem to relate to components of the bacterial surface other than lipopolysaccharides.
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PMID:Somatic antigens of Pseudomonas aeruginosa. The structure of the polysaccharide chain of Ps. aeruginosa O-serogroup 7 (Lanyi) lipopolysacharide. 677 40

An O-antigenic lipopolysaccharide, manifesting a high serological activity in the reaction of passive haemagglutination and its inhibition, was isolated from Pseudomonas aeruginosa O:6 cells (Lanyi). Splitting-off of the lipid component by mild acid hydrolysis resulted in the polysaccharide deprived of O-specific activity. The polysaccharide chain of the lipopolysaccharide was made up exclusively of the residues of amino sugars, among which have been identified: 2-acetamido-2-deoxy-D-galactose (GalNAc), 2-acetamido-2,6-dideoxy-D-glucose (QuiNAc), 2-acetamido-2,6-dideoxy-D-galactose (FucNAc) as well as 2,3-diacetamido-2,3-dideoxy-D-glucuronic acid [Glc(NAc)2A] found naturally for the first time. The principal methods of establishing the polysaccharide structure were 13C nuclear magnetic resonance, methylation analysis and solvolysis with hydrogen fluoride. Depending on solvolysis conditions, a disaccharide or a trisaccharide containing the diacetamidouronic acid residue was formed. From the results obtained it followed that the polysaccharide chain of the O-antigenic Ps. aeruginosa O:6 lipopolysaccharide represents an acidic hexasaminoglycan constructed of the repeating tetrasaccharide units of the following structure: leads to 4)DGalNAc(alpha 1 leads to 4)DGlc(NAc)2A(beta 1 leads to 3)DFucNAc(alpha 1 leads to 3)DQuiNAc(alpha 1 leads to.
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PMID:Somatic Antigens of Pseudomonas aeruginosa. The structure of the polysaccharide chain of Ps.aeruginosa O:6 (Lanyi) lipopolysaccharide. 680 64

Chitin, a linear beta 1-4 linked poly-N-acetylglucosamine, enhanced the in vivo immune response of normal mice to sheep red blood cells, but not that of mice with thymic aplasia (nude mice). The compound is mitogenic for murine B lymphocytes but not for thymocytes or splenic T lymphocytes. Similarly to well-known polyclonal B-lymphocyte activators; e.g. lipopolysaccharide, chitin induces differentiation of B lymphocytes into antibody-forming cells in vitro.
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PMID:Chitin: an immunological adjuvant and a polyclonal B-lymphocyte activator. 698 Jan 93

In Salmonella minnesota lipopolysaccharide the lipid A backbone, a substituted diphosphorylated beta 1,6-linked D-glucosamine disaccharide molecule, carries approximately seven residues of fatty acids: one each of dodecanoic, hexadecanoic, D-3-hydroxytetradecanoic and D-3-O-(tetradecanoyl)-tetradecanoic acid in ester linkage and two of D-3-hydroxytetradecanoic acid in amide linkage. In the present study it is shown that treatment of the lipopolysaccharide with alkali at elevated temperature leads, through a beta-elimination reaction, to the generation of amide-bound delta 2-tetradecanoic acid. This suggested that the 3-hydroxyl group of amide-bound hydroxy fatty acids carried a substituent. To elucidate the nature of the substituent, free Salmonella lipid A was methylated with methyl iodine in the presence of silver salts followed by mild acid hydrolysis, a procedure which is known to cleave amide (and not ester) bonds selectively. In the hydrolysate, by means of combined gas-liquid chromatography/mass spectrometry the methyl esters of 3-O-(dodecanoyl)-tetradecanoic and 3-O-(hexadecanoyl)-tetradecanoic acid were identified. This shows that in lipid A amide-linked 3-hydroxytetradecanoic acid residues are 3-O-acylated by dodecanoic and hexadecanoic acid, respectively. Quantitative analyses suggest that the Salmonella lipid A backbone is substituted by four D-3-hydroxytetradecanoyl residues, two being present as esters and two as amides. The nonhydroxylated fatty acids are not bound directly to the backbone. Rather, they are attached to hydroxyl groups of 3-hydroxytetradecanoyl residues: specifically, tetradecanoic acid substitutes ester-bound and dodecanoic and hexadecanoic acid amide-bound 3-hydroxytetradecanoic acid.
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PMID:The chemical structure of lipid A. Demonstration of amide-linked 3-acyloxyacyl residues in Salmonella minnesota Re lipopolysaccharide. 708 25


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