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

The F6R rough mutants isolated from Shigella flexneri F6S, serotype 5b, and the FH rough mutants, derived from other serotypes of S. flexneri, were chemotyped according to the chemical analysis of their lipopolysaccharides. Further, the following stages of lipopolysaccharide core biosynthesis in S. flexneri have been established: --(KDO)3--heptose--heptose--glucose--galactose; the last three stages are: either --glucose--glucosamine--glucose, or --glucosamine--glucose--glucose. The results of the chemical study of the R lipopolysaccharides are compatible with the assumption of the existence of a similar core in all considered S. flexneri serotypes.
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PMID:[Chemotypes of "Shigella flexneri" R mutants and related phage receptors. I. -- Chemical study of the lipopolysaccharides (author's transl)]. 79 13

The cell envelope of Neisseria gonorrhoeae, colony type 4, was studied. Outer membrane was isolated by lysozyme and ethylenediaminetetraacetic acid treatment of plasmolyzed cells according to Wolf-Watz et al. (1973). The degree of purity of the membrane preparations was checked by electron microscopy. The membrane fraction obtained had a density of 1.25 g/cm(3), was rich in phospholipase A and lysophospholipase, and contained only 10% of the total membrane activity of succinate dehydrogenase and d-lactate dehydrogenase. The outer membrane protein profile after sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed at least six major proteins. The predominating protein showed a molecular weight of 35,000. The lipopolysaccharide component was characterized by gas chromatography. The carbohydrates found were galactose, glucose, and glucosamine. d-Glycero-l-manno-heptose was present in very low amounts. Lipid A contained lauric acid, stearic acid, and beta-hydroxy-myristic acid. About 20% of the fatty acids in the outer membrane was derived from lipid A. The phospholipids were characterized as phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. There was no evidence for a lipoprotein anchored to the peptidoglycan. The peptidoglycan of N. gonorrhoeae was of the chemotype I. The cell envelope of N. gonorrhoeae was found to be highly permeable to gentian violet. Cell envelopes of one penicillin-resistant and two penicillin-sensitive strains were compared. Only moderate differences in fatty acid composition were found.
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PMID:Cell envelope of Neisseria gonorrhoeae: outer membrane and peptidoglycan composition of penicillin-sensitive and-resistant strains. 80 26

Exopolysaccharides were prepared from cultures of four Myxococcus strains grown on solid and in liquid media, and also from the fruiting bodies. Lipopolysaccharides could be extracted with aqueous phenol from the vegetative bacteria, but were absent from microcysts. Mannose and D-glucose were present in all the exopolysaccharides and three of the lipopolysaccharides examined. Other monosaccharides identified in the exopolysaccharides were D-galactose, N-acetylglucosamine and N-acetylgalactosamine. The composition of the lipopolysaccharides was more complex than that of the exopolysaccharides and, in addition to the neutral hexoses and amino sugars, rhamnose was identified in two preparations and ribose in another. No lipopolysaccharide preparations contained O-methyl xylose or heptose. The polysaccharides secreted by the bacillary forms grown on solid or in liquid media closely resembled the polysaccharides isolated from the fruiting bodies, in which they provided a matrix surrounding the microcysts. Each pair of polysaccharides contained the same monosaccharides, although in slightly different proportions. Differences were found in preparations from different strains. These results suggest that in the development cycle of the genus Myxococcus, considerable use is made of pre-existing enzyme systems to synthesize the precursors necessary for polysaccharide synthesis. Any specific difference between the polysaccharide produced by the bacilli and that surrounding the microcysts may lie in the fine structure, rather than in the individual components.
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PMID:Comparison of polysaccharides produced by Myxococcus strains. 80 82

Lipopolysaccharide isolated from pseudomonas aeruginosa PAC1 and its phage-resistant mutant was degraded by mild acid hydrolysis into lipid A and three major polysaccharide-containing fractions which were separated on Sephadex G-75. The low-molecular-weight fraction contained glucose, rhamnose, heptose, galactosamine, alanine and phosphate. The higher-molecular-weight fractions consisted mainly of glucose, rhamnose and glucosamine together with amino compounds. Alkaline degradation of the lipopolysaccharide produced at least four different species each of which contained a low-molecular-weight polysaccharide similar if not identical to that produced by acid hydrolysis. Under certain growth conditions an abnormal lipopolysaccharide was produced which was defective in the low-molecular-weight polysaccharide and contained mainly high-molecular-weight material. Strains of different serotype yielded lipopolysaccharides which also exhibited heterogeneity but contained a low-molecular-weight polysaccharide similar to that obtained from strain PAC1 and PAC1R. It is suggested that each strain of P. aeruginosa may produce several lipopolysaccharides each containing a polysaccharide common to all. The relative proportions of the various lipopolysaccharides may be changed by growth conditions.
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PMID:Heterogeneity of the lipopolysaccharide from Pseudomonas aeruginosa. 81 Mar 51

Two polymeric water-soluble fractions were isolated by gel filtration after mild acid hydrolysis of the lipopolysaccharide from Pseudomonas aeruginosa N.C.T.C. 1999. The fraction of higher molecular weight retained the O-antigenic specificity of the lipopolysaccharide and may be 'side-chain' material. This fraction was rich in N (about 10%) and gave several basic amino compounds on acid hydrolysis; fucosamine (at least 2.8% w/w) was the only specifc component identified. The fraction of lower molecular weight was a phosphorylated polysaccharide apparently corresponding to 'core' material. The major components of this fraction and their approximate molar proportions were: glucose (3-4); rhamnose (1); heptose (2); 3-deoxy-2-octulonic acid (1); galactosamine (1); alanine (1-1.5); phosphorus (6-7). In the intact lipopolysaccharide this fraction was probably linked to lipid A via a second residue of 3-deoxy-2-octulonic acid, and probably also contained additional phosphate residues and ethanolamine. The residues of 3-deoxy-2-octulonic acid were apparently substituted in the C-4 or C-5 position, and the phosphorylated heptose residues in the C-3 position. The rhamnose was mainly 2-substituted, though a little 3-substitution was detected. The glucose residues were either unsubstituted or 6-substituted. Four neutral oligosaccharides were produced by partial acid hydrolysis and were characterized by chemical, enzymic, chromatographic and mass-spectrometric methods of analysis. The structures assigned were: Glcpalpha1-6Glc; Glcpbeta1-2Rha; Rhapalpha1-6Glc; Glcpbeta1-2Rhapalpha1-6Glc. The galactosamine was substituted in the C-3 or C-4 position, the attachment of alanine was indicated, and evidence that the amino sugar linked the glucose-rhamnose region to the 'inner core' was obtained.
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PMID:Studies of polysaccharide fractions from the lipopolysaccharide of Pseudomonas aeruginosa N.C.T.C. 1999. 81 Dec 18

Bacterial lipopolysaccharides extracted from Bacteroides fragilis subspecies fragilis lacked 2-keto-3-deoxyoctonate and heptose, sugars which make up part of the inner core of most bacterial endotoxins. Over 98% of the lipid portion of this material could be removed easily with chloroform-methanol and alcohol, a finding which indicates a loose association between the polysaccharide and lipid moieties. The lipopolysaccharides caused gelation of limulus lysate at a concentration significantly higher than that for the endotoxin of Salmonella typhi. None of the extracts was lethal in 10-day-old chick embryos at doses of greater than 200 mug per egg, whereas the endotoxin of Neisseria meningitidis was lethal at a dose of 1.2 mug per egg. The local Shwartzman reaction could not be induced by levels of B. fragilis endotoxin of up to 1,000 mug per rabbit, whereas a (control) endotoxin of S. typhi induced this phenomenon at a level of 3 mug per rabbit. Intact oxygen-killed B. fragilis failed to provoke the local Shwartzman reaction at doses of 2,500 mug. These results indicate that B. fragilis has a lipopolysaccharide different from that of most gram-negative bacteria. Although it retains some of the chemical and biologic properties of classical endotoxin, it seems to lack others. This observation may have significant clinical implications.
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PMID:Chemical and biological characterization of the lipopolysaccharide of Bacteroides fragilis subspecies fragilis. 93 22

Lipolysaccharide was isolated from Chromatium vinosum by phenol/water extraction. The lipopolysaccharide is found exclusively in the phenol phase and can be cleaved into a sugar moiety and a lipid A fraction by hydrolysis in 10% acetic acid at 100 degrees C for 3-4 h. The sugar moiety contains the neutral sugars 3-O-methyl-D-ribose, D-ribose, L-arabinose, mannosamine and glucose, and smaller quantities of D-rhamnose, D-glycero-D-manno-heptose (tentatively identified), quinovosamine and 2-keto-3-deoxyoctonate. L-glycero-D-manno-heptose was not detected. The 2-keto-3-deoxyoctonate linkage in C. vinosum lipopolysaccharide is more resistant to acid hydrolysis than that of Escherichia coli. The lipid A fraction contains glucosamine, mannose and the fatty acids of the lipopolysaccharide. The major fatty acid is beta-hydroxymyristic acid, with smaller amounts of lauric and palmitic acids as well as 14-carbon mono-unsaturated fatty acid, also being present. The phosphorus content of the C. vinosum lipopolysaccharide was found to be approximately 0.1%. Erythrocytes sensitized with alkali-treated C. vinosum lipopolysaccharide were agglutinated by antisera prepared against heat-killed cells. Untreated or heat-treated lipopolysaccharide did not sensitize erythrocytes. The lethal toxicity to mice of the C. vinosum lipopolysaccharide is about one-tenth as that from Salmonella abortus equi.
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PMID:Isolation and characterization of the lipopolysaccharide of Chromatium vinosum. 97 62

The chemical properties and the general biological activities of lipopolysaccharide (LPS) and Boivin-type endotoxin obtained respectively by phenol-water and trichloroacetic acid extraction from Yersinia enterocolitica serotypes O3 and O9 were studied. The yield of LPS from the O9 strain was about 10% of the O3 strain possibly because of the lower solubility of O9-LPS in aqueous phase. However, the chemical composition of O9-LPS was similar to that of O3-LPS in the proportions of reducing sugar, glucosamine, heptose, KDO, and lipid A. In pyrogenicity and local Shwartzman reactivity in rabbits and lethality for mice, there was also no difference between O3 and O9-LPS. The anthrone-positive carbohydrate and lipid A contents of Boivin-type endotoxin from O3 were higher than those of the endotoxin from O9. The biological activities of Boivin-type endotoxin from O3 were also remarkably higher than those of the endotoxin from O9. It seems that endotoxin of Y. enterocolitica serotype O3 may play an important role in infection by this organism.
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PMID:Biological activities of endotoxins from Yersinia enterocolitica. 97 37

The lipopolysaccharide of Escherichia coli BB and a number of R-phage selected (e.g. T3, T4) cell-wall-defective mutants were analyzed. From their lipopolysaccharides the respective core oligosaccharides were obtained. Following dephosphorylation, the oligosaccharides were methylated and analyzed by gas chromatography/mass spectrometry. This revealed the sugar sequence in the hexose-heptose region of the core. The linkage of heptose (Hep) to 2-keto-3-deoxyoctonate (KDO) was established as ... Hep 1,5 leads to KDO ... by methylation analysis. The substituted derivative of KDO was identified by gas chromatography and mass spectrometry. The KDO region contains three KDO units. Its structure was elaborated by (a) selective removal and identification of 7-phosphoryl ethanolamine-KDO (KDO-PN), (b) periodate oxidation and thiobarbituric acid reaction in conjunction with mild hydrolysis, (c) a modified methylation analysis. Phosphate substitution of E. coli BB core was studied by beta-elimination and using the information obtained with KDO-PN. The structures of the cell wall lipopolysaccharides from E. coli BB and cell-wall-defective mutants are given.
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PMID:Cell-wall lipopolysaccharide from Escherichia coli B. 110 Mar 90

The cell envelope structure of Salmonella typhimurium LT2, which has a heptose-deficient lipopolysaccharide (LPS), is significantly different from that of an isogenic strain with a normal LPS. The rough strain, when examined by freeze-etching, lacks most surface structures that are routinely present in the smooth strain (surface particles and flagella) and has few transmemberane studs in the cytoplasmic membrane (those present are generally found in aggregates), and the outer membrane cleavage is substantially stronger than that of the smooth strain. These envelope differences were independent of both growth temperature and culture age. Examination of ultrathin sections indicated that the rough strain has an outer membrane which forms a much more defined double-track artifact than the smooth strain. The addition of MgCl2 to the growth medium of the rough strain decreased the extent of outer membrane cleavage, and flagella became evident in freeze-etched preparations. The presence of supplemental MgCl2 in the growth medium, which resulted in these morphological changes in the rough strain, also produced growth at a previously restrictive temperature and a decrease in the leakage of periplasmic enzymes. The smooth strain was unaltered morphologically or physiologically by MgCl2 under identical conditions. It is suggested that the outer membrane of the rough strain is more planar.
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PMID:Comparison of the cell envelope structure of a lipopolysaccharide-defective (heptose-deficient) strain and a smooth strain of Salmonella typhimurium. 110 37


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