Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The O-specific polysaccharide obtained from the lipopolysaccharide of Shigella dysenteriae type 1 (Shigella shiga) by mild acid hydrolysis followed by fractionation on Sephadex G-50 was found to be identical to that desribed by Morgan's group and was composed of L-rhamnose, D-galactose and N-acetyl-D-glycosamine in a ratio 2:1:1. On the basis of methylation analysis data the polysaccharide was proved to be a linear chain of monosaccharide residues in pyranose forms substituted at position 3, except for that of galactose substituted at position 2. Selective cleavage, based on the N-deacetylation reaction of the polymer, together with determination of linkage configurations by chromic anhydride oxidation showed that the O-specific polysaccharide is built up of repeating tetrasaccharide units whose proposed structure is given below -3)-alpha-L-Rhap (1-3)-alpha-L-Rhap(1-2)-alpha-D-Galp(1-3)-alphapD-GlcNAcp(1- where RHAP = rhamnopyranose, Galp = galactopyranose, and GlcNAcp = N-acetyl-glucosamine. The present findings confirmed the considerations of Heidelberger on the substitution patterns of L-rhamnose and D-galactose residues from the results of serological studies.
 ...
PMID:Somatic antigens of shigella. Structural investigation on the O-specific polysaccharide chain of Shigella dysenteriae type 1 lipopolysaccharide. 0 14

Among three analyzed serotypes of Shigella dysenteriae, namely, the serotypes 2,4 and 8, the serotype 2 proved to be a strong immunogen in rabbits, inducing anti-polysaccharide antibodies as well as antiprotein antibodies in all the animals. In contrast, the serotypes 4 and 8 were weak immunogens and among the rabbits some have synthesized only anti-proteins while others had antibodies against the somatic conjugate. Aside from the somatic antigens, large amounts of proteins were isolated from all the strains; however, the numerous determinants of these proteins were proven with the help of a serum to proteins from Sh. sonnei. The polysaccharides were specific for the serotype. The sensitivity of Sh. dysenteriae strains to phage P1 and the phage receptor actigity of different bacterial extracts were examined. By using the phage receptor neutralization test, it was possible to demonstrate that the receptor substance is a common component present in the lipopolysaccharide. The nature of neutralization has been discussed.
 ...
PMID:Sh. dysenteriae serotypes2,4,8-immunochemistry and phage receptor activity. 6 97

The O-specific polysaccharide obtained from Shigella dysenteriae type-2 lipopolysaccharide by mild acid hydrolysis consisted of N-acetylgalactosamine, N-acetylglucosamine, D-galactose, D-glucose, and O-acetyl group in the ratio of 2:1:1:1:1. A number of oligosaccharides were obtained by deamination of the N-deacetylated polysaccharide and by Smith degradation of the both native and O-deacetylated polysaccharides. The identification of oligosaccharides along with methylation analysis and chromic anhydride oxidation showed that the polysaccharide was built up of the repeating pentasaccharide units whose proposed structure is given below: (see article) Serological properties of Sh. dysenteriae O-specific polysaccharides are discussed.
 ...
PMID:Somatic antigens of Shigella. Structural investigation on the O-specific polysaccharide chain of Shigella dysenteriae type-2 lipopolysaccharide. 33 Jan 62

The specific polysaccharide was released from Shigella dysenteriae type 5 lipopolysaccharide by mild acidic hydrolysis and then purified by gel chromatography on Sephadex G-50. The polysaccharide was built up of residues of D-mannose, 2-acetamido-2-deoxy-D-glucose, 3-0-(D-1-carboxyethyl)-L-rhamnose (rhamnolactylic acid) and 0-acetyl groups in a ratio 2:1:1:1. On the basis of radiospectroscopy, methylation analysis, Smith degradation, and chromium trioxide oxidation, the repeating oligosaccharide unit of the polysaccharide can be assigned the following structure: (formula: see text) where GlcNAc is 2-acetamido-2-deoxy-D-glucopyranose, Manp is mannopyranose, RhaLcA is rhammolacytic acid and Ac is an acetyl group. The serological properties of Sh. dysenteriae somatic antigens are discussed in relation to the chemical structures of their specific polysaccharides.
 ...
PMID:Somatic antigens of Shigella. The strucuture of the specific polysaccharide chain of Shigella dysenteriae type 5 lipopolysaccharide. 33 37

Two lipopolysaccharide preparations were obtained from Escherichia coli 058 by extraction with 45% aqueous phenol and fractional precipitation with cetyltrimethyl ammonium bromide (Cetavlon). Chemical analysis and polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate showed that the two preparations differed only in the extent of the O-specific polysaccharide moiety. The O-specific polysaccharide was characterized with proton magnetic resonance and infrared spectroscopy, optical rotation and paper electrophoresis. Using gas-liquid chromatography and ion-exchange chromatography, it was shown to contain D-mannose, 2-acetamido-2-deoxy-D-glucose, 3-O-(R-1'-carboxyethyl)-L-rhamnose (rhamnolactylic acid), and O-acetyl groups in the molar ratios of 2:1:1:1. The polysaccharide and oligosaccharides obtained from it were subjected to methylation and chromic acid oxidation. The results obtained indicated that the polysaccharide consists of tetrasaccharide repeating units in which the trisaccharide beta-GlcNAc1 - 4alphaMan-1 - 4(2/3-O-Ac)-Man is substituted at C-3 of the non-acetylated mannose with rhamnolactylic acid. The repeating units are joined through alpha-mannosyl-1 - 3-glucosamine bonds. This structure is identical with that of the cell wall polysaccharide of Shigella dysenteriae type 5.
 ...
PMID:Cell-wall lipopolysaccharide of the 'Shigella-like' Escherichia coli 058. Structure of the polysaccharide chain. 33 42

The natural occurrence of cations Fe, Zn, Mg, and Ca in the lipopolysaccharide (LPS) of both the S and R forms of Shigella dysenteriae 1 was studied. LPS preparations were obtained either by phenol-water extraction (according to the method of Westphal et al., Z. Naturforsch. 7b:148-155, 1952) or by extraction of cells with hypertonic sodium chloride-sodium citrate (according to the method of Raynaud and Digeon, C. R. Acad. Sci. (Paris) 229:564-566, 1949), with subsequent chromatographic purification on Sephadex G200 and Sepharose 4B columns. The cation in highest concentration in the Westphal extract was Mg(2+) (as much as 30 mug/mg), and the lowest one was Fe (ca. 0.10 mug/mg). In LPS of the Raynaud type, the cation in highest concentration was Ca(2+) (as much as 13 mug/mg), and the lowest one was Fe (ca. 0.10 mug/mg). The effects of increasing and decreasing the concentrations of cations (Fe, Zn, Mg, Ca) upon the biological activity of the endotoxins was evaluated by using toxicity in mice and the Limulus test. It appeared that increased concentrations of Fe (chiefly of Fe(3+)) decreased the toxicity of the R form of LPS, whereas Mg(2+) decreased the toxicity of the S form. After prolonged dialysis of LPS preparations against deionized water, there was no consistent relationship between toxicity as determined in white mice and with the Limulus test.
 ...
PMID:Effects of certain cations (Fe, Zn, Mg, and Ca) on bacterial endotoxins. 35 92

Mild acetic acid hydrolysis of endotoxin (lipopolysaccharide-protein complex) of Shigella dysenteriae type 1 (S and R forms) yielded a lipid A-protein complex that consisted of amino acids, fatty acids, and sugar and, in terms of chemical composition, displayed no marked differences between the S and R forms. Its protein portion (53 to 56%) consisted of at least 16 amino acids. In the fatty acid portion (14 to 18%), myristic, 3-hydroxymyristic, palmitic, and stearic acids accounted for 50%. The sugar portion (10 to 12%) consisted solely of glucosamine. The remainder was unidentified substances, most of which contained phosphorus. Lipid A-protein complexes derived from both S and R forms were not toxic for mice in doses up to 1,000 microgram/mouse, but their Linulus test activity had increased considerably as compared with the starting lipopolysaccharide-protein complex material: from 10(-6) to 10(-10--10(-12) mg/ml. The lipid A-protein complexes were readily soluble in a water solution of triethylamine, in dimethyl sulfoxide, and in pyridine.
 ...
PMID:Characteristics of lipid A-protein complex from endotoxin of Shigella dysenteriae type 1 (S and R strains). 37 18

In the course of its isolation and purification, bacterial endotoxin may be contaminated by some inorganic cations. The present study was concerned with Cu-2+ contamination of the lipopolysaccharide-protein complex (LPS) extracted from Shigella dysenteriae 1 S and R strains. The Cu-2+ contamination level of LPS prepared by Raynaud's method and partly purified through Sephadex G200 and Sepharose 4B was in the range of 1-5 mug Cu-2+/mg LPS. Crude Raynauds extract, similarly as LPS prepared by Westphal's method without subsequent purification, contained 0.02-0,1 mug Cu-2+/mg LPS. The linkage of Cu-2+ to LPS was relatively weak; the Cu-2+ content could be substantially reduced, viz. to 0.05-0.1 mug/mg, by dialysis against solutions of suitable complex-forming agents (EDTA, DL-alpha alanine). Neither a grossly augmented (up to 60 mug/mg) nor a lowered Cu-2+ concentration (0.02 mug/mg) had any appreciable influence on the toxicity or other biological properties of LPS. Attention is drawn to this ability of LPS to bind and again readily release a relatively large amount of Cu-2+ and the possibility that this ability is utilized by the bacterial cell in Cu-2+ transport through the cell membrane.
 ...
PMID:The influence of some cations on bacterial endotoxins: copper. 80 51

From Escherichia coli 0124 two lipopolysaccharide preparations were obtained with phenol/water extraction and cetavlon precipitation. Polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate and chemical analysis showed that the two preparations from E. coli 0124 and the corresponding preparations from Shigella dysenteriae type 3 reacted alike. The O-specific polysaccharide moiety was characterized with proton magnetic resonance spectroscopy, optical rotation and paper electrophoresis. The constituents were determined by gas chromatography and ion-exchange chromatography. The polysaccharide contained glucose (Glc), galactose (Gal), galactosamine (GalN) and 4-O-(1'-carboxyethyl)-D-glucopyranose (glucolactilic acid, GlcLA) in the molar ratios of 1:2:1:1. Glucolactilic acid, which has a structure similar to muramic acid, was first found in Sh. dysenteriae. The polysaccharide from E. coli 0124 and oligosaccharides obtained from it by partial acid hydrolysis were subjected to methylation analysis using the method of combined gas chromatography--mass spectrometry. The results indicated that the pentasaccharide repeating unit of the polysaccharide is (see article). In the polysaccharide the repeating units are joined through galactofuranosidic linkages. This structure is identical with that of the somatic polysaccharide of Sh. dysenterae type 3.
 ...
PMID:Cell-wall lipopolysaccharide of the 'Shigella-like' Escherichia coli 0124. Structure of the polysaccharide chain. 81 66

Endotoxins of S and R forms of Shigella dysenteriae 1 were prepared by NaCl-Na citrate extraction, purified by gel chromatography on Sephadex G 200 and on Sepharose 4B and subjected to immunochemical and chemical analysis. The toxins contained 25--30% of lipids, 40--50% of carbohydrates and 14--24% of protein. The lipid and protein moieties of the lipopolysaccharide-protein complexes exhibited no significant difference, whereas the sugar moieties differed markedly (both qualitatively and quantitatively), in relation to the growth form of the culture. The lipid moiety, which consists at least of 22 fatty acids, has the greatest relative content (approx. 50%) of behenic acid, 22:0, and palmitic acid, 16:0 (approx. 11%). In the protein moiety, at least 16 amino acids were determined; these amino acids were identical in both endotoxin types, but their total content was higher in the R form, giving an R:S ratio of 1.7 +/- 0.2. The sugar moiety consists of galactose, glucosamine and either rhamnose (in S endotoxin) or aldoheptose (in R endotoxin). The difference of the chemical composition of the sugar moiety is believed to account for the diametric difference in the immunochemical character, in particular the different behaviour in the electric field, of both endotoxin types. The average content of 3-deoxy-D-manno-2-octulosonic acid was determined as 0.5% for both S and R endotoxin. Trace amounts of O-phosphorylethanolamine were found. Individual aspects of the chemical and immunochemical analysis are discussed in detail.
 ...
PMID:Some immunochemical and chemical aspects of S and R Shigella dysenteriae 1 endotoxins. 110 98


1 2 3 4 5 6 7 8 9 10 Next >>