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

Structural studies were carried out on a rhamnose-rich polysaccharide isolated from the O-polysaccharide fraction of lipopolysaccharide in Pseudomonas aeruginosa IID 1008 (ATCC 27584) after destruction of the major O-specific chain by alkaline treatment. The isolated polysaccharide contained rhamnose, 3-O-methyl-6-deoxyhexose, glucose, xylose, alanine, galactosamine and phosphorus in a molar ratio of 67:6.9:4.3:2.1:1.1:1.0:4.1. Data from analysis involving Smith degradation, methylation, 1H-NMR spectroscopy and optical rotation measurement showed that the polysaccharide was built up of three moieties, a rhamnan chain composed of about 70 D-rhamnose residues, the core chain and an oligosaccharide chain comprising 3-O-methyl-6-deoxyhexose, xylose, rhamnose and probably glucose. The repeating unit of the rhamnan chain was indicated to have the following structure:----3)D-Rha(alpha 1----3)D-Rha(alpha 1----2)D-Rha(alpha 1----. This structure is identical with that proposed previously for the repeating unit of the side chain of lipopolysaccharide from plant pathogenic bacteria Pseudomonas syringae pv. morsprunorum C28 [Smith, A.R.W., Zamze, S.E., Munro, S.M., Carter, K. J. and Hignett, R.C. (1985) Eur. J. Biochem. 149, 73-78].
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PMID:Characterization of a polysaccharide component of lipopolysaccharide from Pseudomonas aeruginosa IID 1008 (ATCC 27584) as D-rhamnan. 311 49

The O-haptens of the major fraction (f5A) of B. abortus (Strains 2308 and 19) membrane bound smooth lipopolysaccharide (sLPS) were prepared by hydrolysis of f5A native sLPS in 1% acetic acid at 100 degrees C for 2 h. After hydrolysis, O-haptens were separated from Lipid A-protein complex by centrifugation, and from small fragments by ultrafiltration of molecular weight cut-off (MWCO) 1.0 X 10(3). These carbohydrate haptens were identified by precipitin-inhibition assay and further fractionated by both membrane filtration and dialysis. The size distributions of carbohydrate haptens of endotoxins (f5A) ranged from oligosaccharides up to polysacchandes of 1.0 X 10(4) MWCO. Three major fractions of MWCO 8.0-10.0 X 10(3), 3.5-5.0 X 10(3) and less than 1.0 X 10(3) from both strains 2308 and 19 contained more than 85% of the total immunoactive materials. These fractions of haptens were subjected to composition, proton and 13C NMR analysis and were found to be a homopolymer of alpha 1----2 linked, 4,5-dideoxy-4-formamido-D-mannose (N-formylperosamine), which is identical to O-haptens of B. abortus strain 119.3 and Yersinia enterocolitica serotype 0:9 and similar to Vibrio cholerae 569B (INABA). Fractions of these haptens exhibited similar inhibitory reactivities in a precipitin-inhibition assay as expressed as mumoles of monosaccharide of anhydro-N-formyl perosamine. They were about 480 times as active as Me alpha----DMan or DMan.
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PMID:Structural and immunochemical characterization of the O-haptens of Brucella abortus lipopolysaccharides from strains 19 and 2308. 311 17

Cyclic (1----2)-beta-D-glucan was isolated from killed cells of pathogenic Brucella melitensis 16M. Its structure was deduced mainly from the acid hydrolysis, methylation analysis and 13C-NMR spectroscopy data. The cycloglucan and demicellated lipopolysaccharide of B. melitensis 16M form a stable complex identical, by immunodiffusion test, to the earlier described polysaccharide B antigen.
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PMID:[Molecular nature of the Brucella polysaccharide antigen (poly-B)]. 311 86

Structural studies were carried out on an acidic O-polysaccharide released by mild acid treatment from the lipopolysaccharide of Pseudomonas aeruginosa IID 1001 (ATCC 27577), which is serologically related to the serotypes Habs O3, Lanyi O1, and Wokatsch O13 in other serological classifications of Pseudomonas aeruginosa. The composition and data from structural analyses including H-NMR and C-NMR measurements, methylation, and Smith degradation showed that the structure of the IID 1001 O-polysaccharide was coincident with that of the Habs O3 and Lanyi O1 antigens (or Wokatsch O13). However, whereas solvolysis of the O-antigen of Habs O3 as well as that of Lanyi O1 by hydrogen fluoride has been reported to yield a reducing trisaccharide, GlcNAc(alpha 1----4)GalNAcA(alpha 1----3)Bac2NAc4Nacyl (acyl represents a 3-hydroxybutanoyl group), hydrogen fluoride hydrolysis of IID 1001 O-polysaccharide yielded a nonreducing trisaccharide with the reducing terminal bacillosamine residue linked at C-1 to the hydroxyl group of its N-acyl substituent, 3-hydroxybutanoic acid. These results, in combination with mass spectral data, led to the most likely structure for the tetrasaccharide repeating unit of the IID 1001 O-polysaccharide, (formula; see text) in which the location of N-acyl groups on bacillosamine residues differs from that in the O-antigens of Habs O3 and Lanyi O1 (or Wokatsch O13).
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PMID:Structure of the O-polysaccharide chain of lipopolysaccharide from Pseudomonas aeruginosa IID 1001 (ATCC 27577). 314 81

The chemical structure of the lipopolysaccharide of a deep-rough mutant (strain I-69 Rd-/b+) of Haemophilus influenzae was investigated. The hydrophilic backbone of lipid A was shown to consist of a beta-(1',6)-linked D-glucosamine disaccharide with phosphate groups at C-1 of the reducing D-glucosamine and at C-4' of the non-reducing one. Four molecules of (R)-3-hydroxytetradecanoic acid were found directly linked to the lipid A backbone, two by amide and two by ester linkage (positions 2,2' and 3,3', respectively). Laser-desorption mass spectrometry showed that both 3-hydroxytetradecanoic acids linked to the non-reducing glucosamine carry tetradecanoic acid at their 3-hydroxyl group, so that altogether six molecules of fatty acid are present in lipid A. The lipopolysaccharide was the first described to contain only one sugar unit linked to lipid A. This, sugar in accordance with a previous report [Zamze et al. (1987) Biochem. J. 245, 583-587], was shown to be a dOclA phosphate. The phosphate group was found at position 4, but the analytical procedures employed (permethylation and methanolysis followed by gas-liquid chromatography/mass spectrometry) also revealed dOclA 5-phosphate. Since a cyclic 4,5-phosphate could be ruled out by 31P-NMR, we conclude that, in this lipopolysaccharide, a mixture of dOclA 4- and 5-phosphate is present. By methylation analysis of the dephosphorylated, deacylated and reduced lipopolysaccharide the attachment site of the dOclA was assigned to position C-6' of the non-reducing glucosamine of lipid A. The anomeric linkages present in the lipopolysaccharide were assessed by 1H-NMR and 13C-NMR of deacylated lipopolysaccharide. The saccharide backbone of this Haemophilus influenzae lipopolysaccharide possesses the following structure: (Formula; see text)
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PMID:Chemical structure of the lipopolysaccharide of Haemophilus influenzae strain I-69 Rd-/b+. Description of a novel deep-rough chemotype. 326 41

The structure of the 4-amino-L-arabinose-lacking lipopolysaccharide of the Proteus mirabilis Rc-type mutant R4, derived from wild-type O28, was elucidated. The lipopolysaccharide core structure has previously been partially characterized. The linkage between heptose and deoxyoctulosonic acid(dOclA) is now reported, as well as the structure of the lipid A moiety of this mutant strain. Besides the tentative identification of an alpha-linked glucosamine disaccharide in the lipid A backbone accompanying the usual beta 1----6-linked glucosamine-disaccharide, the only significant structural variation to previous studies was the lack of substitution of the C-4' phosphate by 4-amino-L-arabinose. In addition, the substitution at C-8 of one dOclA unit by 4-amino-L-arabinose, previously reported for the R45 mutant of P. mirabilis 1959, is lacking in this R mutant. Also in addition to previous findings, the terminal unit of heptose was found to be substituted at C-7 with phosphorylethanolamine (PEtN) and not only with phosphate, although this substitution is not complete as demonstrated by the relevant signals in 31P-NMR. Additional studies with the wild-type strain P. mirabilis O28 revealed the presence of 4-amino-L-arabinose in both the core and the lipid A regions suggesting that the R4 mutant is defective in the biosynthesis of this amino sugar rather than in its transfer. Otherwise the lipid A regions of the mutant and the wild-type strain show no structural differences. The following formula is proposed for the lipopolysaccharide of 4-amino-L-arabinose-lacking mutant R4/O28 P. mirabilis: (Formula; see text)
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PMID:Structural studies on the core and lipid A region of a 4-amino-L-arabinose-lacking Rc-type mutant of Proteus mirabilis. 328 Mar 11

A polymeric fraction containing the putative O-antigen has been isolated from the lipopolysaccharide of the reference strain (CDC 4534-60) for serogroup O9 of Serratia marcescens. The major component of the fraction was a polymer with a disaccharide repeating-unit of L-rhamnose (Rha) and 2-acetamido-2-deoxy-D-galactose (GalNAc) with the following structure:----3)D-GalpNAc(beta 1----3)L-Rhap(alpha 1----. Evidence for the presence in the fraction of a similar, minor polymer containing 4-substituted rhamnose residues was provided by the NMR spectra, methylation analysis, and Smith degradation.
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PMID:Structural studies of the putative O-specific polysaccharide of Serratia marcescens O9. 330 42

The complete structure of the 0-specific polysaccharide of the strain Proteus mirabilis S 1959, as analyzed by 13C NMR, is presented. Some data demonstrating the significant heterogeneity of the 0-specific chain in the investigated lipopolysaccharide are also described.
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PMID:Structure of the 0-specific polysaccharide of Proteus mirabilis S 1959. 332 44

The Brucella M antigen from the species type strain Brucella melitensis 16M has been identified as a component of the cell wall lipopolysaccharide (LPS). O polysaccharide liberated from this LPS by mild acid hydrolysis exhibited M activity in serological tests and was shown to be a homopolymer of 4-formamido-4,6-dideoxy-alpha-D-mannopyranosyl residues arranged in an oligosaccharide repeating unit as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the native lipopolysaccharide. Structural analysis of the O polysaccharide by NMR methods was difficult due to apparent microheterogeneity of the repeating unit, which was in fact caused by the presence of rotational isomers of the N-formyl moiety. This problem was resolved by chemical modification of the polysaccharide to its amino and N-acetyl derivatives, the 500-MHz 1H and 125-MHz 13C NMR spectra of which could be analyzed in terms of a unique structure through application of pH-dependent beta-shifts and two-dimensional techniques that included COSY, relayed COSY, and NOESY experiments together with heteronuclear C/H shift correlation spectroscopy. On the basis of these experiments and supported by methylation and periodate oxidation data, the structure of the M polysaccharide was determined as a linear polymer of unbranched pentasaccharide repeating units consisting of four 1,2-linked and one 1,3-linked 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl residues. The marked structural similarity of the M antigen and the A antigen, which is known to be a 1,2-linked homopolysaccharide of 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units, accounts for cross-serological reactions of the two and the long-standing confusion surrounding the nature of their antigenic determinants. Structural and serological considerations in conjuction with the sodium dodecyl sulfate banding pattern of Brucella A LPS suggest that its biosynthesis differs appreciably from that of the M antigen, which appears to be synthesized by regulated assembly of preformed oligosaccharide repeating units. Temperature, lysogenic phage may be responsible for such biosynthetic and structural variations.
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PMID:Structural elucidation of the Brucella melitensis M antigen by high-resolution NMR at 500 MHz. 344 84

Preliminary studies from our laboratory have suggested the existence of a novel set of fatty acyltransferases in extracts of Escherichia coli that attach two R-3-hydroxymyristoyl moieties to UDP-GlcNAc (Anderson, M.S., Bulawa, C.E., and Raetz, C.R.H. (1985) J. Biol. Chem. 260, 15536-15541). The resulting "glucosamine-derived" phospholipids appear to be crucial precursors for the biosynthesis of the lipid A component of lipopolysaccharide. We now describe an assay and a 1000-fold purification of the first enzyme in this pathway, which catalyzes the reaction: UDP-GlcNAc + R-3-hydroxymyristoyl-acyl carrier protein----UDP-3-O-(R-3-hydroxymyristoyl)-GlcNAc + acyl carrier protein. The covalent structure of the monoacylated UDP-GlcNAc product was established by fast atom bombardment mass spectrometry and 1H-NMR spectroscopy. The UDP-GlcNAc acyltransferase has a strict requirement for R-3-hydroxymyristoyl-acyl carrier protein, since R-3-hydroxymyristoyl coenzyme A and myristoyl-acyl carrier protein are not substrates. Of various NDP-GlcNAc preparations examined, only the uridine and thymidine derivatives were utilized to a significant extent. When the product of the reaction (UDP-3-O-(R-3-hydroxymyristoyl)-GlcNAc) was isolated and reincubated with crude E. coli extracts, it was rapidly converted to more hydrophobic products in the presence of R-3-hydroxymyristoyl-acyl carrier protein. We propose that the addition of an R-3-hydroxymyristoyl residue to the 3 position of the GlcNAc moiety of UDP-GlcNAc is the first committed step in lipid A biosynthesis and that UDP-GlcNAc is situated at a biosynthetic branchpoint in E. coli leading either to lipid A or to peptidoglycan.
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PMID:Biosynthesis of lipid A precursors in Escherichia coli. A cytoplasmic acyltransferase that converts UDP-N-acetylglucosamine to UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine. 354 16


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