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

An O antigenic polymer containing L-rhamnose, D-mannose, and L-xylose was isolated from the lipopolysaccharide present in the reference strain for Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia serogroup O2, by mild acid hydrolysis and gel-permeation chromatography. By means of NMR spectroscopy and chemical degradations, the polysaccharide was found to be based on a branched trisaccharide repeating-unit of the structure shown. [formula: see text].
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PMID:Structure of the O2 antigen of Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia. 909 Aug 15

Lipopolysaccharide and extracellular glyco polymers were isolated from cells of phytopathogenic bacteria Ralstonia solanacearum. It was established that the O-specific polysaccharides are characterized by a linear structure, composed of tetrasaccharide repeating units containing three L-rhamnose residues and one of N-acetylglucosamine residue. Core oligosaccharide along with typical monosaccharides such as rhamnose, glucose, heptose, KDO and glucosamine included fucose, galactose and arabinose. Serological activity of lipopolysaccharide is due to both O-specific polysaccharide and lipid A component. Extracellular glyco polymers contained both neutral (GP 1) and charged (GP 2 and GP 3) components. Rhamnose and glucose (GP 1, GP 2) or galactose (GP 3) were predominant monosaccharides, GP 2 displayed a high phytotoxic action in respect to tomato plants.
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PMID:[The chemical composition and biological activity of the glyco polymers in Ralstonia solanacearum (Yabuchi et al., 1995)]. 948 12

The lipopolysaccharides LPS I and LPS II, isolated from the hypovirulent EV40 strain of Yersinia pestis, are composed only of type R lipopolysaccharides. This type consists of two forms a and b, depending on their solubility pattern in a solvent mixture containing varying proportions of chloroform, methanol, hexane, and hydrochloric acid. LPS I consists of one subtype, RIb, while LPS II consists of two subtypes, RIIa and RIIb. Analysis by gel electrophoresis shows that the mass of these lipopolysaccharide forms are in the vicinity of 2000-3000 Da. The RIb and RIIb subtypes, which are found in the majority of lipopolysaccharide I and II fractions, are composed of ketoses and amines that are similar to those occurring in LPS I and LPS II. In contrast, the two subtypes RIIa and RIIb are different both in terms of the composition of lipid A and the extent of its substitution. Certain fractions of RIIa contain only lipid A and 3-deoxy-D-manno-octulosonic acid (KDO), while other fractions of RIIb possess a lipid A, which is not substituted by arabinose. The whole set of these R-type lipopolysaccharide forms are excellent models for the study of the role of the primary structure of the polysaccharide region, and for the effect of lipid A substitution on the biological activity of bacterial lipopolysaccharides.
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PMID:[Isolation and chemical characterization of type R lipopolysaccharides of a hypovirulent strain of Yersinia pestis]. 974 73

Species- and genus-specific antigenic determinants of total serological activity of plague agent lipopolysaccharide (LPS) were detected for the first time with a panel of monoclonal antibodies (MAb) in Y. pestis core polysaccharide in the R-form. MAb specifically bind radicals on one or several monosaccharides of core LPS. Galactose, fucose, and mannose contain common antigenic determinants for enterobacteria; glucosamine, glucose, ribose, xylose, and 2-ketodeoxyoctanoic acid (KDO) contain determinants for Y. pestis and Y. pseudotuberculosis; and epitopes differentiating the two latter agents by the carbohydrate component are localized on glucosamine, mannose, xylose, and KDO. Epitopes common for the Enterobacteriaceae family and species-specific epitopes, two of which are identic to core polysaccharide radicals, are situated on Y. pestis lipid A.
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PMID:[Study of antigenic determinants of Yersinia pestis lipopolysaccharide using monoclonal antibodies]. 981 23

A neutral polysaccharide was obtained by hot phenol-water extraction of biomass from Campylobacter jejuni 176.83 and subsequently separated from acid-liberated core oligosaccharide of lipopolysaccharide by sequential GPC on Bio-Gel P6 and TSK-40 columns. All sugar components of the trisaccharide repeating unit of the polysaccharide were found to be of the furanose ring form. The major trisaccharide contained beta-L-arabinose, 6-deoxy-beta-D-altro-heptose (beta-D-6d-altHep) and 6-deoxy-beta-L-altrose (beta-L-6d-Alt), whereas in the minor trisaccharide the beta-L-6d-Alt is replaced by its C-5 epimer alpha-D-Fuc. On the basis of 1H and 13C NMR spectroscopic studies, including 2D ROESY, HMQC and HMQC-TOCSY experiments, the following structures of the repeating units were established: [formula: see text]
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PMID:Chemical structure of a polysaccharide from Campylobacter jejuni 176.83 (serotype O:41) containing only furanose sugars. 1052 Feb 60

The O-chain polysaccharide (OPS) of the lipopolysaccharide of Xanthomonas campestris pv. begoniae GSPB 525 was found to contain L-rhamnose and L-xylose in the ratio 1:0.6. The OPS lacked strict regularity because of nonstoichiometric xylosylation of the main rhamnan chain. Based on methylation analysis, Smith degradation, and 1H and 13C NMR spectroscopy, including COSY, TOCSY, NOESY, and H-detected 1H,13C heteronuclear multiple-quantum coherence (HMQC) experiments, the following structure of the OPS was established: [formula: see text].
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PMID:The O-chain polysaccharide of the lipopolysaccharide of Xanthomonas campestris pv. begoniae GSPB 525 is a partially L-xylosylated L-rhamnan. 1052 Feb 63

Non-virulent Ara+ B. pseudomallei environmental isolates differ from virulent Ara- clinical isolates by their ability to assimilate L-arabinose and the absence of a 200 kDa antigen on their surface. The latter, present only on the Ara- isolates from either clinical or environmental origin, was recently demonstrated by its immunoreactivity with monoclonal antibody (MAb) 5F8. We recently demonstrated that lipopolysaccharide (LPS) from both biotypes were indistinguishable from one another with regard to SDS-PAGE profiles and immunoreactivities with immune sera. In this study, the shedding of LPS and 200-kDa antigen into the culture medium during the in vitro growth of Ara- was compared with that of its Ara+ counterpart, using MAb-based sandwich ELISAs. The results showed that the LPS shedding profiles from the two biotypes were similar to one another. This was in contrast to the situation with the 5F8-reactive antigen. The culture fluid of all Ara- isolates and none of the Ara+ isolates were found to react strongly with the MAb 5F8 during the early log phase of growth. However, during the late stationary phase, a trace amount of the 5F8-reactive material could also be detected in the culture fluid of the Ara+ isolates.
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PMID:Shedding of lipopolysaccharide and 200-kDa surface antigen during the in vitro growth of virulent Ara- and avirulent Ara+ Burkholderia pseudomallei. 1067 53

The O-chain polysaccharide of the lipopolysaccharide of Xanthomonas campestris pv. manihotis strains GSPB 2755 and GSPB 2364 was studied by sugar and methylation analyses and 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, NOESY, and H-detected 1H, 13C heteronuclear multiple-quantum coherence (HMQC) experiments. The polysaccharide was found to contain L-rhamnose and L-xylose in the ratio 3:1, and the following structure of the tetrasaccharide repeating unit was established: [formula: see text]
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PMID:Structure of the O-chain polysaccharide of the lipopolysaccharide of Xanthomonas campestris pv. manihotis GSPB 2755 and GSPB 2364. 1078 8

When Escherichia coli are grown on LB broth containing 25 mm NH(4)VO(3), complex modifications to the lipid A anchor of lipopolysaccharide are induced. Six modified lipid As (EV1-EV6) have been purified. Many of these variants possess 4-amino-4-deoxy-l-arabinose (l-Ara4N) and/or phosphoethanolamine (pEtN) substituents. Here we use NMR spectroscopy to investigate the attachment sites of the l-Ara4N and pEtN moieties on underivatized, intact EV3 and EV6 and on precursors II(A) and III(A) from kdsA mutants of Salmonella. CDCl(3)/CD(3)OD/D(2)O (2:3:1, v/v) is shown to be a superior solvent for homo- and heteronuclear one- and two-dimensional NMR experiments. The latter were not feasible previously because available solvents caused sample decomposition. Selective inverse decoupling difference spectroscopy is used to determine the attachment sites of substituents on EV3, EV6, II(A), and III(A). l-Ara4N is attached via a phosphodiester linkage to the 4'-phosphates of EV3 and EV6 and has the beta anomeric configuration. pEtN is attached by a pyrophosphate linkage to the 1-phosphate of EV6. The l-Ara4N and pEtN substituents of lipids II(A) and III(A) are attached in the opposite manner, with l-Ara4N on the 1-phosphate of II(A) and pEtN on the 4'-phosphate of III(A). Determination of the proper attachment sites of these substituents is necessary for elucidating the enzymology of lipid A biosynthesis and for characterizing polymyxin-resistant mutants, in which l-Ara4N and pEtN substituents are greatly increased.
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PMID:High-resolution NMR spectroscopy of lipid A molecules containing 4-amino-4-deoxy-L-arabinose and phosphoethanolamine substituents. Different attachment sites on lipid A molecules from NH4VO3-treated Escherichia coli versus kdsA mutants of Salmonella typhimurium. 1078 69

The PhoP-PhoQ two-component system is necessary for the virulence of Salmonella spp. and is responsible for regulating several modifications of the lipopolysaccharide (LPS). Mutagenesis of the transcriptional regulator phoP resulted in the identification of a mutant able to activate transcription of regulated genes approximately 100-fold in the absence of PhoQ. Sequence analysis showed two single-base alterations resulting in amino acid changes at positions 93 (S93N) and 203 (Q203R). These mutations were individually created, and although each resulted in a constitutive phenotype, the double mutant displayed a synergistic effect both in the induction of PhoP-activated gene expression and in resistance to antimicrobial peptides. The constitutive phoP gene was placed under the control of an arabinose-inducible promoter to examine the kinetics of PhoP-activated gene induction and the resultant modifications of LPS. Gene induction and 2-hydroxymyristate modification of the lipid A were shown to occur within minutes of the addition of arabinose and to peak at 4 h. As the first constitutive mutant of phoP identified, this allele will be invaluable to future genetic and biochemical studies of this and likely other regulatory systems.
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PMID:Constitutive mutations of the Salmonella enterica serovar Typhimurium transcriptional virulence regulator phoP. 1081 43


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