Show legend Show as text

Structure type: oligomer
Aglycon: lipid A
Contained glycoepitopes: IEDB_115136,IEDB_130650,IEDB_130699,IEDB_136045,IEDB_137485,IEDB_140630,IEDB_142489,IEDB_144562,IEDB_144983,IEDB_152206,IEDB_152214,IEDB_174333,IEDB_983930,SB_44,SB_72,SB_86

• Article ID: 78
  Forsberg LS, Bhat UR, Carlson RW "Structural characterization of the O-antigenic polysaccharide of the lipopolysaccharide from Rhizobium etli strain CE3. A unique O-acetylated glycan of discrete size, containing 3-O-methyl-6-deoxy-L-talose and 2,3,4-tri-O-methyl-L-fucose" - Journal of Biological Chemistry 275(25) (2000) 18851-18863
  

  The O-antigenic polysaccharide of the Rhizobium etli CE3 lipopolysaccharide (LPS) was structurally characterized using chemical degradations (Smith degradation and beta-elimination of uronosyl residues) in combination with alkylation analysis, electrospray, and matrix-assisted laser desorption ionization-time of flight mass spectrometry, tandem mass spectrometry, and (1)H COSY and TOCSY nuclear magnetic resonance spectroscopy analyses of the native polysaccharide and the derived oligosaccharides. The polysaccharide was found to be a unique, relatively low molecular weight glycan having a fairly discrete size, with surprisingly little variation in the number of repeating units (degree of polymerization = 5). The polysaccharide is O-acetylated and contains a variety of O-methylated glycosyl residues, rendering the native glycan somewhat hydrophobic. The molecular mass of the major de-O-acetylated species, including the reducing end 3-deoxy-d-manno-2-octulosonic acid (Kdo) residue, is 3330 Da. The polysaccharide is comprised of a trisaccharide repeating unit having the structure →4)-α-D-GlcpA-(1→4)-[α-3-O-Me-6-deoxy-Talp-(1→3)]-α-l-Fucp-(1→. The nonreducing end of the glycan is terminated with the capping sequence α-2,3,4-tri-O-Me-Fucp-(1→4)-α-D-GlcpA-(1→, and the reducing end of the molecule consists of the non-repeating sequence →3)-α-L-Fucp-(1→3)-β-D-Manp-(1→3)-β-QuiNA cp-(1→4)-alpha-Kdop-(2→, where QuiNAc is N-acetylquinovosamine (2-N-acetamido-2,6-dideoxyglucose). The reducing end Kdo residue links the O-chain polysaccharide to the core region oligosaccharide, resulting in a unique location for a Kdo residue in LPS, removed four residues distally from the lipid A moiety. Structural heterogeneity in the O-chain arises mainly from the O-acetyl and O-methyl substitution. Methylation analysis using trideuteriomethyl iodide indicates that a portion of the 2,3,4-tri-O-methylfucosyl capping residues, typically 15%, are replaced with 2-O-methyl- and/or 2,3-di-O-methylfucosyl residues. In addition, approximately 25% of the 3,4-linked branching fucosyl residues and 10% of the 3-linked fucosyl residues are 2-O-methylated. A majority of the glucuronosyl residues are methyl-esterified at C-6. These unique structural features may be significant in the infection process

  Lipopolysaccharide, O-antigen, Rhizobium etli, 6-deoxy-L-talose, symbiosis

  NCBI PubMed ID: 10858446
  Publication DOI: 10.1074/jbc.M001090200
  Journal NLM ID: 2985121R
  Publisher: Baltimore, MD: American Society for Biochemistry and Molecular Biology
  Correspondence: rcarlson@ccrc.uga.edu
  Institutions: Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA, USA
  Methods: methylation, sugar analysis, ESI-MS, ESI-MS/MS
  
   
  
  Rhizobium etli CE3
  CSDB ID 2182 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: repeating unit of OPS
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_142489,IEDB_144562,IEDB_152214,IEDB_174333,SB_86

• Article ID: 79
  Forsberg LS, Noel KD, Box J, Carlson RW "Genetic locus and structural characterization of the biochemical defect in the O-antigenic polysaccharide of the symbiotically deficient Rhizobium etli mutant, CE166: Replacement of N-acetylquinovosamine with its hexosyl-4-ulose precursor" - Journal of Biological Chemistry 278(51) (2003) 51347-51359
  

  The O-antigen polysaccharide (OPS) of Rhizobium etli CE3 lipopolysaccharide (LPS) is linked to the core oligosaccharide via an N-acetylquinovosaminosyl (QuiNAc) residue. A mutant of CE3, CE166, produces LPS with reduced amounts of OPS, and a suppressed mutant, CE166α, produces LPS with nearly normal OPS levels. Both mutants are deficient in QuiNAc production. Characterization of OPS from CE166 and CE166α showed that QuiNAc was replaced by its 4-keto derivative, 2-acetamido-2,6-dideoxyhexosyl-4-ulose. The identity of this residue was determined by NMR and mass spectrometry, and by gas chromatography-mass spectrometry analysis of its 2-acetamido-4-deutero-2,6-dideoxyhexosyl derivatives produced by reduction of the 4-keto group using borodeuteride. Mass spectrometric and methylation analyses showed that the 2-acetamido-2,6-dideoxyhexosyl-4-ulosyl residue was 3-linked and attached to the core-region external Kdo III residue of the LPS, the same position as that of QuiNAc in the CE3 LPS. DNA sequencing revealed that the transposon insertion in strain CE166 was located in an open reading frame whose predicted translation product, LpsQ, falls within a large family of predicted open reading frames, which includes biochemically characterized members that are sugar epimerases and/or reductases. A hypothesis to be tested in future work is that lpsQ encodes UDP-2-acetamido-2,6-dideoxyhexosyl-4-ulose reductase, the second step in the synthesis of UDP-QuiNAc from UDP-GlcNAc

  Lipopolysaccharide, NMR, genetic, synthesis, LPS, oligosaccharide, core, DNA, strain, structural, characterization, polysaccharide, O-antigen, analysis, O antigen, group, linked, locus, O-antigenic, O-antigenic polysaccharide, Kdo, core oligosaccharide, level, spectrometry, mutant, mutants, Rhizobia, Rhizobium, Rhizobium etli, sugar, core region, biochemical, derivative, DNA sequencing, epimerase, external, families, gas chromatography-mass spectrometry, insertion, mass spectrometry, methylation, Open Reading Frames, position, precursor, production, reduced, reduction, sequencing, translation, transposon

  NCBI PubMed ID: 14551189
  Journal NLM ID: 2985121R
  Publisher: Baltimore, MD: American Society for Biochemistry and Molecular Biology
  Correspondence: rcarlson@ccrc.uga.edu
  Institutions: Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA, USA
  Methods: NMR-2D, methylation, NMR, sugar analysis, MS
  
   
  
  Rhizobium etli CE3
  CSDB ID 2073 (all data & tools)

Show legend Show as text

Structure type: oligomer
Compound class: core oligosaccharide
Contained glycoepitopes: IEDB_115136,IEDB_130650,IEDB_130699,IEDB_130701,IEDB_136045,IEDB_137485,IEDB_140630,IEDB_142489,IEDB_144562,IEDB_144983,IEDB_152206,IEDB_152214,IEDB_174333,IEDB_983930,SB_44,SB_67,SB_72,SB_86

• Article ID: 1418
  Duelli DM, Tobin A, Box JM, Kolli VSK, Carlson RW, Noel KD "Genetic locus required for antigenic maturation of Rhizobium etli CE3 lipopolysaccharide" - Journal of Bacteriology 183(20) (2001) 6054-6064
  

  Rhizobium etli modifies lipopolysaccharide (LPS) structure in response to environmental signals, such as low pH and anthocyanins. These LPS modifications result in the loss of reactivity with certain monoclonal antibodies. The same antibodies fail to recognize previously isolated R. etli mutant strain CE367, even in the absence of such environmental cues. Chemical analysis of the LPS in strain CE367 demonstrated that it lacked the terminal sugar of the wild-type O antigen, 2,3,4-tri-O-methylfucose. A 3-kb stretch of DNA, designated as lpe3, restored wild-type antigenicity when transferred into CE367. From the sequence of this DNA, five open reading frames were postulated. Site-directed mutagenesis and complementation analysis suggested that the genes were organized in at least two transcriptional units, both of which were required for the production of LPS reactive with the diagnostic antibodies. Growth in anthocyanins or at low pH did not alter the specific expression of gusA from the transposon insertion of mutant CE367, nor did the presence of multiple copies of lpe3 situated behind a strong, constitutive promoter prevent epitope changes induced by these environmental cues. Mutations of the lpe genes did not prevent normal nodule development on Phaseolus vulgaris and had very little effect on the occupation of nodules in competition with the wild-type strain.

  Lipopolysaccharide, genetic, antigenic, locus, Rhizobia, Rhizobium, Rhizobium etli

  NCBI PubMed ID: 11567006
  Publication DOI: 10.1128/JB.183.20.6054-6064.2001
  Journal NLM ID: 2985120R
  Publisher: American Society for Microbiology
  Correspondence: Dale.Noel@marquette.edu
  Institutions: Department of Biology,Marquette University, Wisconsin, USA
  Methods: genetic methods
  
   
  
  Rhizobium etli CE3
  CSDB ID 6602 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: N-acylpeptide LIP(1-2)xDPhe(1-2)xDaThr(1-2)xDAla?(1-2)Subst // Subst = alaninol = SMILES N{2}[C@@H](C){1}CO
Trivial name: oligosaccharide hapten
Compound class: glycopeptidolipid (GPL)
Contained glycoepitopes: IEDB_115136,IEDB_130699,IEDB_136045,IEDB_136105,IEDB_140630,IEDB_142489,IEDB_144562,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_423153,IEDB_885823,SB_86

• Article ID: 1450
  Chatterjee D, Khoo KH "The surface glycopeptidolipids of mycobacteria: structures and biological properties" - Cellular and Molecular Life Sciences 58(14) (2001) 2018-2042
  

  One of the most important opportunistic pathogens associated with acquired immunodeficiency syndrome (AIDS) is the M. avium complex. M. avium infections are found in up to 70% of individuals in advanced stages of AIDS. It is apparent that M. avium can replicate in host macrophages and persist for long periods. This group of mycobacteria are distinguished by the presence of unique, highly antigenic, surface- located lipids known as the glycopeptidolipids (GPLs). The GPLs are the chemical basis of the 31 distinct serovars of the M. avium complex, and have also been identified in some other species. The M. avium lipids are immunosuppressive and can induce a variety of cytokines that affect general host responses. Despite extensive chemical characterization of the structures of these GPLs, much work is needed to elucidate the molecular mechanism involved in this complex glycosylation pathway and its genetic basis. The challenges for the future lie in explaining the roles of these copious products in the intracellular life and infectivity of mycobacteria. The intention of our review is to offer a concise account of the structures of the M. avium lipids, their putative roles in the host responses, bacterial physiology and pathogenesis, particularly in immunocompromised patients such as those infected with human immunodeficiency virus (HIV). Advances in chemical synthesis of the various haptenic oligosaccharides are also given to demonstrate how these have helped to define the immunogenic determinants. We believe that future research should involve the creation of conditional mutants defective in these lipids for both functional and biosynthesis studies which will complement biological assays using chemically defined or modified neoglycoconjugates

  Mycobacteria, neoglycoproteins, glycopeptidolipid (GPL), Mycobacterium avium complex (MAC), haptenic oligosaccharides

  NCBI PubMed ID: 11814054
  Publication DOI: 10.1007/PL00000834
  Journal NLM ID: 9705402
  Publisher: Basel: Springer
  Correspondence: delphi@lamar.colostate.edu
  Institutions: Department of Microbiology, Colorado State University, Fort Collins 80523, USA, Institute of Biological Chemistry, Academia Sinica, Taipei (Taiwan)
  
   
  
  Mycobacterium avium sv. 26
  CSDB ID 31663 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: Phenolphthiocerol dimycocerosate
Compound class: glycolipid
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_136105,IEDB_142489,IEDB_144562,IEDB_151530,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_885823,SB_86

• Article ID: 1790
  Daffé M "Further specific triglycosyl phenol phthiocerol diester from Mycobacterium tuberculosis" - Biochimica et Biophysica Acta 1002 (1989) 257-260
  
  Journal NLM ID: 0217513
  Publisher: Elsevier
  Methods: 1H NMR
  
   
  
  Mycobacterium tuberculosis
  CSDB ID 109219 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: phenolphthiocerol A dimycocerosate
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_136105,IEDB_142489,IEDB_144562,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_885823,SB_86

• Article ID: 1795
  Watanabe M, Yamada Y, Iguchi K, Minnikin DE "Structural elucidation of new phenolic glycolipids from Mycobacterium tuberculosis" - Biochimica et Biophysica Acta 1210 (1994) 174-180
  

  From one clinical isolate of Mycobacterium tuberculosis, two new phenolic glycolipids(PGLs) were obtained as its major PGLs. These were dimycocerosyl esters of 2,4-di-O-methyl-fucopyranosyl-(α1→3)-rhamnopyranosyl-(α1→3)-2-O-methyl-rhamnopyranosyl-(α1→)-phenolphthiocerol A and -phenolphthiotriol A, which were produced by this strain at a ratio of about 5:1. Another clinical isolate of this species was found to produce PGL-tb1 and its analogue, 2,3,4-tri-O-methyl-fucopyranosyl-(α1→3)-rhamnopyranosyl-(α1→3)-2-O-methyl-rhamnopyranosyl-(α1→)-phenolphthiotriol A at a ratio of about 1:3. The fact that different strains of M. tuberculosis produce chemically different PGLs as their major PGLs may be related to the diversity of virulence of the clinical isolates of M. tuberculosis.

  NCBI PubMed ID: 8280767
  Journal NLM ID: 0217513
  Publisher: Elsevier
  Institutions: Research Institute of BCG, Tokyo, Japan
  Methods: 13C NMR, 1H NMR
  
   
  
  Mycobacterium tuberculosis
  CSDB ID 109501 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: phenolphthiotriol A dimycocerosate
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_136105,IEDB_142489,IEDB_144562,IEDB_151530,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_885823,SB_86

• Article ID: 1795
  Watanabe M, Yamada Y, Iguchi K, Minnikin DE "Structural elucidation of new phenolic glycolipids from Mycobacterium tuberculosis" - Biochimica et Biophysica Acta 1210 (1994) 174-180
  

  From one clinical isolate of Mycobacterium tuberculosis, two new phenolic glycolipids(PGLs) were obtained as its major PGLs. These were dimycocerosyl esters of 2,4-di-O-methyl-fucopyranosyl-(α1→3)-rhamnopyranosyl-(α1→3)-2-O-methyl-rhamnopyranosyl-(α1→)-phenolphthiocerol A and -phenolphthiotriol A, which were produced by this strain at a ratio of about 5:1. Another clinical isolate of this species was found to produce PGL-tb1 and its analogue, 2,3,4-tri-O-methyl-fucopyranosyl-(α1→3)-rhamnopyranosyl-(α1→3)-2-O-methyl-rhamnopyranosyl-(α1→)-phenolphthiotriol A at a ratio of about 1:3. The fact that different strains of M. tuberculosis produce chemically different PGLs as their major PGLs may be related to the diversity of virulence of the clinical isolates of M. tuberculosis.

  NCBI PubMed ID: 8280767
  Journal NLM ID: 0217513
  Publisher: Elsevier
  Institutions: Research Institute of BCG, Tokyo, Japan
  Methods: 13C NMR, 1H NMR
  
   
  
  Mycobacterium tuberculosis
  CSDB ID 109502 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: phenolphthiocerol dimycocerosate
Trivial name: phenylethanoid glycoside
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_136105,IEDB_142489,IEDB_144562,IEDB_151530,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_885823,SB_86

• Article ID: 1796
  Hartmann S, Minnikin DE, Mallet AI, Ridell M, Rigouts L, Portaels F "Fast atom bombardment mass spectrometry of mycobacterial phenolic glycolipids" - Biological Mass Spectrometry 23 (1994) 362-368
  

  Fast atom bombardment mass spectra were successfully recorded for intact glycosylphenolphthiocerol dimycocerosates (phenolic glycolipids, PGLs) from Mycobacterium kansasii, M. leprae, M. tuberculosis, M. marinum, M. bovis and M. haemophilum. Characteristic fragment ions from the loss of the oligosaccharide moiety and one of the long-chain multimethyl-branched mycocerosic acids were observed in most cases. A tandem mass spectrometric experiment was carried out on the PGL from M. tuberculosis, revealing the type of mycocerosic acids esterified to individual homologues. Mass spectra of homologues separated by reversed-phase high-performance liquid chromatography gave information on the substitution pattern in certain cases. The potential of matrix-assisted laser desorption ionization spectroscopy was demonstrated by a successful analysis of the PGL from M. tuberculosis.

  NCBI PubMed ID: 8038230
  Journal NLM ID: 9102982
  Institutions: Department of Chemistry, The University, Newcastle upon Tyne, UK
  Methods: FAB-MS
  
   
  
  Mycobacterium tuberculosis
  CSDB ID 110030 (all data & tools)

Show legend Show as text

Structure type: oligomer
Compound class: chemical synthesis
Contained glycoepitopes: IEDB_115136,IEDB_130699,IEDB_136045,IEDB_136105,IEDB_140630,IEDB_142489,IEDB_144562,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_423153,IEDB_885823,SB_86

• Article ID: 2235
  Aspinall GO, Gammon DW, Sood RK, Chatterjee D, Rivoire B, Brennan PJ "Structures of the glycopeptidolipid antigens of serovars 25 and 26 of the Mycobacterium avium serocomplex, synthesis of allyl glycosides of the outer disaccharide units and serology of the derived neoglycoproteins" - Carbohydrate Research 237 (1992) 57-77
  

  The pentasaccharide hapten released from the glycopeptidolipid (GPL) antigen of M. auium serovar26 has been characterized as O-(2,4-di-O-methyl-α-l-fucopyranosyl)-(1 → 4)-O-β-d-gluco-pyranosyluronic acid-(1 → 4)-O-(2-O-methyl-α-l-fucopyranosyl)-(1 → 3)-α-l-rhamnopyranosyl-(1 #x02192; 2)-6-deoxy-l-talose. The allyl glycosides of the outer glycosyl and glycobiosyl units of this hapten have been synthesized, the latter by a route involving oxidation of the corresponding d-glucopyranose derivative. Conjugation of allyl glycosides to protein by ozonolysis and reductive coupling afforded neoantigens (neo 26−1 and 26−2), both of which interacted with antibodies to M. avium serovar 26. The terminal sugar residue of the pentasaccharide hapten of the serovar 25 GPL had been shown to have the galacto configuration on the basis of 1H-13C NMR correlation spectroscopy, but absolute configurational assignment for the sugar awaited the synthesis, as for neo 26, of two glycobiosyl NGPs bearing the terminal sugar in the d and l enantiomeric forms, respectively. Only the glycobiosyl NGP bearing the terminal sugar as the d-enantiomer interacted with antibodies to M. avium serovar 25, thus providing evidence for the absolute configuration of the sugar, and showing that the complete oligosaccharide hapten has the structure, O-(4-acetamido-4,6-dideoxy-2-O-methyl-α-d-galactopyranosyl)-(1 → 4)-O-β-d-glucopyranosyluronic acid-(1 → 4)-O-(2-O-methyl-α-l-fucopyranosyl)-(1 → 3)-O-α-l-rhamnopyranosyl-(1 → 2)-6-deoxy-l-talose.

  Publication DOI: 10.1016/S0008-6215(92)84233-I
  Journal NLM ID: 0043535
  Publisher: Elsevier
  Institutions: Department of Chemistry, York University, North York, Toronto, Ontario M3J 1P3, Canada
  Methods: chemical synthesis
  
   
  
  Mycobacterium avium 26
  CSDB ID 116998 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: unknown
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_136105,IEDB_142489,IEDB_144562,IEDB_151530,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_885823,SB_86

• Article ID: 2406
  Daffé M, Lacave C, Lanéelle MA, Lanéelle G "Structure of the major triglycosyl phenol-pthiocerol of Mycobacterium tuberculosis (strain Canetti)" - European Journal of Biochemistry 167 (1987) 155-160
  
  Journal NLM ID: 0107600
  Publisher: Oxford, UK: Blackwell Science Ltd. on behalf of the Federation of European Biochemical Societies
  Methods: 13C NMR, 1H NMR, EI-MS
  
   
  
  Mycobacterium tuberculosis
  CSDB ID 123048 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: phenolphthiocerol dimycocerosate
Compound class: glycolipid
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_136105,IEDB_1394181,IEDB_142489,IEDB_144562,IEDB_145010,IEDB_151530,IEDB_152214,IEDB_174333,IEDB_225177,IEDB_885823,SB_86

• Article ID: 2419
  Daffé M, Servin P "Scalar, dipolar-correlated and J-resolved 2D-NMR spectroscopy of the specific phenolic mycoside of Mycobacterium tuberculosis" - European Journal of Biochemistry 185 (1989) 157-162
  
  Journal NLM ID: 0107600
  Publisher: Oxford, UK: Blackwell Science Ltd. on behalf of the Federation of European Biochemical Societies
  Methods: 1H NMR, NMR-2D
  
   
  
  Mycobacterium tuberculosis Canetti
  CSDB ID 123344 (all data & tools)

Show legend Show as text

Structure type: oligomer
Compound class: LPS
Contained glycoepitopes: IEDB_115136,IEDB_130650,IEDB_130659,IEDB_130699,IEDB_130701,IEDB_136045,IEDB_136906,IEDB_137340,IEDB_137472,IEDB_140630,IEDB_141794,IEDB_141807,IEDB_142489,IEDB_144562,IEDB_144983,IEDB_151528,IEDB_151531,IEDB_152206,IEDB_152214,IEDB_174333,IEDB_190606,IEDB_983930,SB_44,SB_67,SB_7,SB_72,SB_86

• Article ID: 3415
  D'Haeze W, Leoff C, Freshour G, Noel KD, Carlson RW "Rhizobium etli CE3 bacteroid lipopolysaccharides are structurally similar but not identical to those produced by cultured CE3 bacteria" - Journal of Biological Chemistry 282(23) (2007) 17101-17113
  

  Rhizobium etli CE3 bacteroids were isolated from Phaseolus vulgaris root nodules. The LPS from the bacteroids was purified and compared with the LPS from laboratory-cultured R. etli CE3 and from cultures grown in the presence of anthocyanin. Comparisons were made of the O-chain polysaccharide, the core oligosaccharide, and the lipid A. It was found that, while LPS from CE3 bacteria and bacteroids are structurally similar, bacteroid LPS had specific modifications to both the O-chain polysaccharide and lipid A portions of their LPS. Cultures grown with anthocyanin contained modifications only to the O-chain polysaccharide. The changes to the O-chain polysaccharide consisted of the addition of a single methyl group to the 2-position of a fucosyl residue in one of the five O-chain trisaccharide repeat units. This same change occurred for bacteria grown in the presence of anthocyanin. This methylation change correlated with the inability of bacteroid LPS and LPS from anthocyanin-containing cultures to bind the monoclonal antibody, JIM28. The core oligosaccharide region of bacteroid LPS and from anthocyanin-grown cultures was identical to that of LPS from normal laboratory-cultured CE3. The lipid A from bacteroids consisted exclusively of a tetraacylated species compared to the presence of both tetra- and pentaacylated lipid A from laboratory cultures. Growth in the presence of anthocyanin did not affect the lipid A structure. Purified bacteroids that could resume growth were also found to be more sensitive to the cationic peptides, poly-L-lysine, polymyxin-B, and melittin

  Lipopolysaccharide, lipid A, monoclonal antibodies, Rhizobium etli, modification, root nodules

  NCBI PubMed ID: 17420254
  Publication DOI: 10.1074/jbc.M611669200
  Journal NLM ID: 2985121R
  Publisher: Baltimore, MD: American Society for Biochemistry and Molecular Biology
  Correspondence: rcarlson@ccrc.uga.edu
  Institutions: Complex Carbohydrate Research Center, The University of Georgia, Athens, GA 30602
  Methods: GC-MS, mild acid hydrolysis, MALDI-TOF MS, composition analysis, serological methods, electron microscopy, immunoblotting
  
   
  
  Rhizobium etli CE3
  CSDB ID 22048 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: core-lipid A
Compound class: LPS
Contained glycoepitopes: IEDB_115136,IEDB_130650,IEDB_130699,IEDB_136045,IEDB_137485,IEDB_140630,IEDB_142489,IEDB_144562,IEDB_144983,IEDB_152206,IEDB_152214,IEDB_174333,IEDB_983930,SB_44,SB_72,SB_86

• Article ID: 3468
  Forsberg LS, Carlson RW "Structural characterization of the primary O-antigenic polysaccharide of the Rhizobium leguminosarum 3841 lipopolysaccharide and identification of a new 3-acetimidoylamino-3-deoxyhexuronic acid glycosyl component: a unique O-methylated glycan of uniform size, containing 6-deoxy-3-O-methyl-D-talose, n-acetylquinovosamine, and rhizoaminuronic acid (3-acetimidoylamino-3-deoxy-D-gluco-hexuronic acid)" - Journal of Biological Chemistry 283(23) (2008) 16037-16050
  

  Rhizobium are Gram-negative bacteria that survive intracellularly, within host membrane-derived plant cell compartments called symbiosomes. Within the symbiosomes the bacteria differentiate to bacteroids, the active form that carries out nitrogen fixation. The progression from free-living bacteria to bacteroid is characterized by physiological and morphological changes at the bacterial surface, a phase shift with an altered array of cell surface glycoconjugates. Lipopolysaccharides undergo structural changes upon differentiation from the free living to the bacteroid (intracellular) form. The array of carbohydrate structures carried on lipopolysaccharides confer resistance to plant defense mechanisms and may serve as signals that trigger the plant to allow the infection to proceed. We have determined the structure of the major O-polysaccharide (OPS) isolated from free living Rhizobium leguminosarum 3841, a symbiont of Pisum sativum, using chemical methods, mass spectrometry, and NMR spectroscopy analysis. The OPS is composed of several unusual glycosyl residues, including 6-deoxy-3-O-methyl-d-talose and 2-acetamido-2deoxy-l-quinovosamine. In addition, a new glycosyl residue, 3-acetimidoylamino-3-deoxy-d-gluco-hexuronic acid was identified and characterized, a novel hexosaminuronic acid that does not have an amino group at the 2-position. The OPS is composed of three to four tetrasaccharide repeating units of →4)-β-dGlcp3NAmA-(1→4)-[2-O-Ac-3-O-Me-α-D-6dTalp-(1→3)]-α-l-Fucp-(1→3)-α-L-QuipNAc-(1→. The unique 3-amino hexuronate residue, rhizoaminuronic acid, is an attractive candidate for selective inhibition of OPS synthesis

  O-antigenic polysaccharide, Rhizobium leguminosarum, nitrogen fixation

  NCBI PubMed ID: 18387959
  Journal NLM ID: 2985121R
  Publisher: Baltimore, MD: American Society for Biochemistry and Molecular Biology
  Correspondence: rcarlson@ccrc.uga.edu
  Institutions: Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30605, USA
  Methods: 13C NMR, 1H NMR, NMR-2D, GC-MS, acid hydrolysis, MALDI-TOF MS, composition analysis, alkaline hydrolysis, ESI-QTOF-MS
  
   
  
  Rhizobium etli CE3
  CSDB ID 22949 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: core-lipid A
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_130699,IEDB_136045,IEDB_137485,IEDB_142489,IEDB_144562,IEDB_144983,IEDB_152206,IEDB_152214,IEDB_174333,IEDB_983930,SB_44,SB_72,SB_86

• Article ID: 3829
  Carlson RW, Forsberg LS, Kannenberg EL "Lipopolysaccharides in Rhizobium-Legume Symbioses" - Book: Endotoxins: Structure, Function and Recognition (series: Subcellular Biochemistry, 2010, Part 1) (2010) Vol. 53, Chapter 16, 339-386
  

  The establishment of nitrogen-fixing symbiosis between a legume plant and its rhizobial symbiont requires that the bacterium adapt to changing conditions that occur with the host plant that both promotes and allows infection of the host root nodule cell, regulates and resists the host defense response, permits the exchange of metabolites, and contributes to the overall health of the host. This adaptive process involves changes to the bacterial cell surface and, therefore, structural modifications to the lipopolysaccharide (LPS). In this chapter, we describe the structures of the LPSs from symbiont members of the Rhizobiales, the genetics and mechanism of their biosynthesis, the modifications that occur during symbiosis, and their possible functions.

  biosynthesis, lipopolysaccharides, structure, Rhizobium, symbiosis, plant defense

  NCBI PubMed ID: 20593275
  Publication DOI: 10.1007/978-90-481-9078-2_16
  Publisher: Springer Science+Business Media B.V.
  Correspondence: rcarlson@ccrc.uga.edu
  Editors: Wang X, Quinn PJ
  Institutions: Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Rd., Athens, GA 30602, USA
  
   
  
  Rhizobium etli CE3
  CSDB ID 25566 (all data & tools)

Show legend Show as text

Structure type: oligomer
Aglycon: core-lipid A
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_115015,IEDB_130650,IEDB_130699,IEDB_136045,IEDB_137485,IEDB_142489,IEDB_144562,IEDB_144983,IEDB_149135,IEDB_152206,IEDB_152214,IEDB_174333,IEDB_983930,SB_44,SB_72,SB_86

• Article ID: 3868
  Kabanov DS, Prokhorenko IR "Structural analysis of lipopolysaccharides from Gram-negative bacteria" - Biochemistry (Moscow) 75(4) (2010) 383-404
  

  This review covers data on composition and structure of lipid A, core, and O-polysaccharide of the known lipopolysaccharides from Gram-negative bacteria. The relationship between the structure and biological activity of lipid A is discussed. The data on roles of core and O-polysaccharide in biological activities of lipopolysaccharides are presented. The structural homology of some oligosaccharide sequences of lipopolysaccharides to gangliosides of human cell membranes is considered.

  core, Lipooligosaccharide, O-antigen, lipid A, gangliosides, cytokines, lipopolysaccharide (endotoxin)

  NCBI PubMed ID: 20618127
  Publication DOI: 10.1134/S0006297910040012
  Journal NLM ID: 0376536
  Publisher: Nauka/Interperiodica
  Correspondence: kabanovd1@rambler.ru
  Institutions: Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Russia
  
   
  
  Rhizobium etli CE3
  CSDB ID 25707 (all data & tools)