Show legend Show as text

Structure type: oligomer
Compound class: core oligosaccharide with O-unit
Contained glycoepitopes: IEDB_115576,IEDB_120354,IEDB_123890,IEDB_130648,IEDB_130650,IEDB_130695,IEDB_130701,IEDB_136105,IEDB_136906,IEDB_137472,IEDB_137473,IEDB_137778,IEDB_140116,IEDB_140529,IEDB_141794,IEDB_142488,IEDB_144983,IEDB_144998,IEDB_146664,IEDB_151528,IEDB_152206,IEDB_164174,IEDB_190606,IEDB_225177,IEDB_474450,IEDB_76933,IEDB_885823,IEDB_983930,IEDB_983931,SB_192,SB_197,SB_44,SB_67,SB_7,SB_72

• Article ID: 3752
  Paramonov NA, Aduse-Opoku J, Hashim A, Rangarajan M, Curtis MA "Structural Analysis of the Core-Region of O-Lipopolysaccharide of Porphyromonas gingivalis from mutants defective in O-antigen ligase and O-antigen polymerase" - Journal of Bacteriology 191(16) (2009) 5272-5282
  

  Porphyromonas gingivalis synthesizes two lipopolysaccharides (LPSs), O-LPS and A-LPS. Here, we elucidate the structure of the core oligosaccharide (OS) of O-LPS from two mutants of P. gingivalis W50, Delta PG1051 (WaaL, O-antigen ligase) and Delta PG1142 (O-antigen polymerase), which synthesize R-type LPS (core devoid of O antigen) and SR-type LPS (core plus one repeating unit of O antigen), respectively. Structural analyses were performed using one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy in combination with composition and methylation analysis. The outer core OS of O-LPS occurs in two glycoforms: an "uncapped core," which is devoid of O polysaccharide (O-PS), and a "capped core," which contains the site of O-PS attachment. The inner core region lacks L(D)-glycero-D(l)-manno-heptosyl residues and is linked to the outer core via 3-deoxy-D-manno-octulosonic acid, which is attached to a glycerol residue in the outer core via a monophosphodiester bridge. The outer region of the "uncapped core" is attached to the glycerol and is composed of a linear alpha-(1→3)-linked d-Man OS containing four or five mannopyranosyl residues, one-half of which are modified by phosphoethanolamine at position 6. An amino sugar, alpha-D-allosamine, is attached to the glycerol at position 3. In the "capped core," there is a three- to five-residue extension of alpha-(1→3)-linked Man residues glycosylating the outer core at the nonreducing terminal residue. beta-D-GalNAc from the O-PS repeating unit is attached to the nonreducing terminal Man at position 3. The core OS of P. gingivalis O-LPS is therefore a highly unusual structure, and it is the basis for further investigation of the mechanism of assembly of the outer membrane of this important periodontal bacterium.

  Lipopolysaccharide, NMR, structure, mutants, core region, O-antigen polymerase, Porphyromonas gingivalis

  NCBI PubMed ID: 19525343
  Publication DOI: 10.1128/JB.00019-09
  Journal NLM ID: 2985120R
  Publisher: American Society for Microbiology
  Correspondence: m.rangarajan@gmul.ac.uk
  Institutions: Queen Mary University of London, Barts and The London School of Medicine & Dentistry, Centre for Infectious Disease, Institute of Cell and Molecular Science, 4 Newark Street, London E1 2AT, United Kingdom
  Methods: 13C NMR, 1H NMR, methylation, NMR-2D, GC-MS, SDS-PAGE, sugar analysis, dephosphorylation, 31P NMR, Western blotting, NMR-1D, genetic methods
  
   
  
  Porphyromonas gingivalis PG1142
  CSDB ID 24153 (all data & tools)

Show legend Show as text

Structure type: oligomer
Compound class: core oligosaccharide
Contained glycoepitopes: IEDB_115576,IEDB_120354,IEDB_123890,IEDB_130650,IEDB_130695,IEDB_130701,IEDB_137778,IEDB_140116,IEDB_144983,IEDB_152206,IEDB_164174,IEDB_474450,IEDB_76933,IEDB_983930,SB_197,SB_44,SB_67,SB_72

• Article ID: 3752
  Paramonov NA, Aduse-Opoku J, Hashim A, Rangarajan M, Curtis MA "Structural Analysis of the Core-Region of O-Lipopolysaccharide of Porphyromonas gingivalis from mutants defective in O-antigen ligase and O-antigen polymerase" - Journal of Bacteriology 191(16) (2009) 5272-5282
  

  Porphyromonas gingivalis synthesizes two lipopolysaccharides (LPSs), O-LPS and A-LPS. Here, we elucidate the structure of the core oligosaccharide (OS) of O-LPS from two mutants of P. gingivalis W50, Delta PG1051 (WaaL, O-antigen ligase) and Delta PG1142 (O-antigen polymerase), which synthesize R-type LPS (core devoid of O antigen) and SR-type LPS (core plus one repeating unit of O antigen), respectively. Structural analyses were performed using one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy in combination with composition and methylation analysis. The outer core OS of O-LPS occurs in two glycoforms: an "uncapped core," which is devoid of O polysaccharide (O-PS), and a "capped core," which contains the site of O-PS attachment. The inner core region lacks L(D)-glycero-D(l)-manno-heptosyl residues and is linked to the outer core via 3-deoxy-D-manno-octulosonic acid, which is attached to a glycerol residue in the outer core via a monophosphodiester bridge. The outer region of the "uncapped core" is attached to the glycerol and is composed of a linear alpha-(1→3)-linked d-Man OS containing four or five mannopyranosyl residues, one-half of which are modified by phosphoethanolamine at position 6. An amino sugar, alpha-D-allosamine, is attached to the glycerol at position 3. In the "capped core," there is a three- to five-residue extension of alpha-(1→3)-linked Man residues glycosylating the outer core at the nonreducing terminal residue. beta-D-GalNAc from the O-PS repeating unit is attached to the nonreducing terminal Man at position 3. The core OS of P. gingivalis O-LPS is therefore a highly unusual structure, and it is the basis for further investigation of the mechanism of assembly of the outer membrane of this important periodontal bacterium.

  Lipopolysaccharide, NMR, structure, mutants, core region, O-antigen polymerase, Porphyromonas gingivalis

  NCBI PubMed ID: 19525343
  Publication DOI: 10.1128/JB.00019-09
  Journal NLM ID: 2985120R
  Publisher: American Society for Microbiology
  Correspondence: m.rangarajan@gmul.ac.uk
  Institutions: Queen Mary University of London, Barts and The London School of Medicine & Dentistry, Centre for Infectious Disease, Institute of Cell and Molecular Science, 4 Newark Street, London E1 2AT, United Kingdom
  Methods: 13C NMR, 1H NMR, methylation, NMR-2D, GC-MS, SDS-PAGE, sugar analysis, dephosphorylation, 31P NMR, Western blotting, NMR-1D, genetic methods
  
   
  
  Porphyromonas gingivalis PG1051
  CSDB ID 24154 (all data & tools)

Show legend Show as text

Structure type: oligomer
Trivial name: uncapped core oligosaccharide
Compound class: core oligosaccharide
Contained glycoepitopes: IEDB_115576,IEDB_120354,IEDB_123890,IEDB_130650,IEDB_130695,IEDB_130701,IEDB_137778,IEDB_140116,IEDB_144983,IEDB_152206,IEDB_164174,IEDB_474450,IEDB_76933,IEDB_983930,SB_197,SB_44,SB_67,SB_72

• Article ID: 3752
  Paramonov NA, Aduse-Opoku J, Hashim A, Rangarajan M, Curtis MA "Structural Analysis of the Core-Region of O-Lipopolysaccharide of Porphyromonas gingivalis from mutants defective in O-antigen ligase and O-antigen polymerase" - Journal of Bacteriology 191(16) (2009) 5272-5282
  

  Porphyromonas gingivalis synthesizes two lipopolysaccharides (LPSs), O-LPS and A-LPS. Here, we elucidate the structure of the core oligosaccharide (OS) of O-LPS from two mutants of P. gingivalis W50, Delta PG1051 (WaaL, O-antigen ligase) and Delta PG1142 (O-antigen polymerase), which synthesize R-type LPS (core devoid of O antigen) and SR-type LPS (core plus one repeating unit of O antigen), respectively. Structural analyses were performed using one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy in combination with composition and methylation analysis. The outer core OS of O-LPS occurs in two glycoforms: an "uncapped core," which is devoid of O polysaccharide (O-PS), and a "capped core," which contains the site of O-PS attachment. The inner core region lacks L(D)-glycero-D(l)-manno-heptosyl residues and is linked to the outer core via 3-deoxy-D-manno-octulosonic acid, which is attached to a glycerol residue in the outer core via a monophosphodiester bridge. The outer region of the "uncapped core" is attached to the glycerol and is composed of a linear alpha-(1→3)-linked d-Man OS containing four or five mannopyranosyl residues, one-half of which are modified by phosphoethanolamine at position 6. An amino sugar, alpha-D-allosamine, is attached to the glycerol at position 3. In the "capped core," there is a three- to five-residue extension of alpha-(1→3)-linked Man residues glycosylating the outer core at the nonreducing terminal residue. beta-D-GalNAc from the O-PS repeating unit is attached to the nonreducing terminal Man at position 3. The core OS of P. gingivalis O-LPS is therefore a highly unusual structure, and it is the basis for further investigation of the mechanism of assembly of the outer membrane of this important periodontal bacterium.

  Lipopolysaccharide, NMR, structure, mutants, core region, O-antigen polymerase, Porphyromonas gingivalis

  NCBI PubMed ID: 19525343
  Publication DOI: 10.1128/JB.00019-09
  Journal NLM ID: 2985120R
  Publisher: American Society for Microbiology
  Correspondence: m.rangarajan@gmul.ac.uk
  Institutions: Queen Mary University of London, Barts and The London School of Medicine & Dentistry, Centre for Infectious Disease, Institute of Cell and Molecular Science, 4 Newark Street, London E1 2AT, United Kingdom
  Methods: 13C NMR, 1H NMR, methylation, NMR-2D, GC-MS, SDS-PAGE, sugar analysis, dephosphorylation, 31P NMR, Western blotting, NMR-1D, genetic methods
  
   
  
  Porphyromonas gingivalis PG1051
  CSDB ID 24155 (all data & tools)
• Article ID: 4781
  Paramonov N, Aduse-Opoku J, Hashim A, Rangarajan M, Curtis MA "Identification of the Linkage between A-Polysaccharide and the Core in the A-LPS of Porphyromonas gingivalis W50" - Journal of Bacteriology 197(10) (2015) 1735-1746
  

  Porphyromonas gingivalis synthesizes two lipopolysaccharides (LPS), O-LPS and A-LPS. The structure of the core oligosaccharide (OS) of O-LPS and the attachment-site of O-polysaccharide (PS) repeating unit [ →3)-α-D-Galp-(1→6)-α-D-Glcp-(1→4)-α-L-Rhap-(1→3)-β-D-GalNAcp-(1→] to the core, have been elucidated using mutant strains ∆PG1051(WaaL, O-antigen ligase) and ∆PG1142 (Wzy, O-antigen polymerase) respectively. The core OS occurs as an 'uncapped' glycoform devoid of O-PS and a 'capped' glycoform which contains the attachment-site of O-PS via β-D-GalNAc at position O-3 of the terminal α-(1→3)-linked mannose (Man) residue. In this study, the attachment site of A-PS to core-OS was determined based on structural analysis of SR-type-LPS [O-LPS and A-LPS] isolated from P. gingivalis mutant strain ∆PG1142 by extraction with aqueous hot-phenol to minimize the destruction of A-LPS. Application of one- and two-dimensional nuclear magnetic resonance spectroscopy (NMR) in combination with methylation analysis showed that A-PS repeating unit is linked to a non-terminal α-(1→3)-linked Man of the 'capped core' glycoform of outer core-OS at position O-4 via →6)-[α-D-Man-α-(1→2)-α-D-Man-1-phosphate→2]-α-D-Man-(1→ motif. In order to verify that O-PS and A-PS are attached to almost identical core glycoforms, we identified a putative α-mannosyltransferase (PG0129) in P. gingivalis W50 which may be involved in the formation of core-OS. Inactivation of PG0129 led to the synthesis of deep-R-type LPS with a truncated core which lacks α-(1→3)-linked mannoses and devoid of either O-PS or A-PS. This indicated that PG0129 is an α-1,3-mannosyltransferase required for synthesis of the outer core-region of both O- and A-LPS in P. gingivalis. IMPORTANCE: Porphyromonas gingivalis, a gram-negative anaerobe is considered to be an important aetiologic agent in periodontal disease and among the virulence factors produced by this organism are two lipopolysaccharides (LPS), O-LPS and A-LPS. The structures of O-PS and A-PS repeating-units, core-oligosaccharide (OS) and linkage of O-PS repeating unit to core-OS in O-LPS have been elucidated by our group. It is important to establish whether the attachment-site of A-PS repeating-unit to core-OS in A-LPS is similar to or differs from that of O-PS repeating-unit in O-LPS. As part of understanding the biosynthetic pathway of the two LPS in P. gingivalis, PG0129 was identified as an α-mannosyltransferase which is involved in the synthesis of the outer-core region of both O-LPS and A-LPS.

  core oligosaccharide, O-antigen polymerase, virulence factor, Porphyromonas gingivalis, A-lipopolysaccharides, A-LPS, O-LPS, A-polysaccharide

  NCBI PubMed ID: 25733619
  Publication DOI: 10.1128/JB.02562-14
  Journal NLM ID: 2985120R
  Publisher: American Society for Microbiology
  Correspondence: m.rangarajan@qmul.ac.uk (Minnie Rangarajan)
  Institutions: Institute of Dentistry, Turner Street, London E1 2AD Centre for Immunology and Infectious Disease, Blizard Institute, 4, Newark Street, London E1 2AT, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, United Kingdom
  Methods: 13C NMR, 1H NMR, methylation, NMR-2D, PCR, GC-MS, SDS-PAGE, DNA techniques, acid hydrolysis, GLC, Western blotting, composition analysis, NMR-1D, methanolysis, GPC
  
   
  
  Porphyromonas gingivalis ∆PG1051
  CSDB ID 30825 (all data & tools)

Show legend Show as text

Structure type: oligomer
Trivial name: capped core oligosaccharide
Compound class: core oligosaccharide
Contained glycoepitopes: IEDB_115576,IEDB_120354,IEDB_123890,IEDB_130650,IEDB_130695,IEDB_130701,IEDB_136104,IEDB_137778,IEDB_140116,IEDB_141111,IEDB_143632,IEDB_144983,IEDB_152206,IEDB_164174,IEDB_164176,IEDB_474450,IEDB_76933,IEDB_983930,SB_136,SB_196,SB_197,SB_44,SB_67,SB_72

• Article ID: 4781
  Paramonov N, Aduse-Opoku J, Hashim A, Rangarajan M, Curtis MA "Identification of the Linkage between A-Polysaccharide and the Core in the A-LPS of Porphyromonas gingivalis W50" - Journal of Bacteriology 197(10) (2015) 1735-1746
  

  Porphyromonas gingivalis synthesizes two lipopolysaccharides (LPS), O-LPS and A-LPS. The structure of the core oligosaccharide (OS) of O-LPS and the attachment-site of O-polysaccharide (PS) repeating unit [ →3)-α-D-Galp-(1→6)-α-D-Glcp-(1→4)-α-L-Rhap-(1→3)-β-D-GalNAcp-(1→] to the core, have been elucidated using mutant strains ∆PG1051(WaaL, O-antigen ligase) and ∆PG1142 (Wzy, O-antigen polymerase) respectively. The core OS occurs as an 'uncapped' glycoform devoid of O-PS and a 'capped' glycoform which contains the attachment-site of O-PS via β-D-GalNAc at position O-3 of the terminal α-(1→3)-linked mannose (Man) residue. In this study, the attachment site of A-PS to core-OS was determined based on structural analysis of SR-type-LPS [O-LPS and A-LPS] isolated from P. gingivalis mutant strain ∆PG1142 by extraction with aqueous hot-phenol to minimize the destruction of A-LPS. Application of one- and two-dimensional nuclear magnetic resonance spectroscopy (NMR) in combination with methylation analysis showed that A-PS repeating unit is linked to a non-terminal α-(1→3)-linked Man of the 'capped core' glycoform of outer core-OS at position O-4 via →6)-[α-D-Man-α-(1→2)-α-D-Man-1-phosphate→2]-α-D-Man-(1→ motif. In order to verify that O-PS and A-PS are attached to almost identical core glycoforms, we identified a putative α-mannosyltransferase (PG0129) in P. gingivalis W50 which may be involved in the formation of core-OS. Inactivation of PG0129 led to the synthesis of deep-R-type LPS with a truncated core which lacks α-(1→3)-linked mannoses and devoid of either O-PS or A-PS. This indicated that PG0129 is an α-1,3-mannosyltransferase required for synthesis of the outer core-region of both O- and A-LPS in P. gingivalis. IMPORTANCE: Porphyromonas gingivalis, a gram-negative anaerobe is considered to be an important aetiologic agent in periodontal disease and among the virulence factors produced by this organism are two lipopolysaccharides (LPS), O-LPS and A-LPS. The structures of O-PS and A-PS repeating-units, core-oligosaccharide (OS) and linkage of O-PS repeating unit to core-OS in O-LPS have been elucidated by our group. It is important to establish whether the attachment-site of A-PS repeating-unit to core-OS in A-LPS is similar to or differs from that of O-PS repeating-unit in O-LPS. As part of understanding the biosynthetic pathway of the two LPS in P. gingivalis, PG0129 was identified as an α-mannosyltransferase which is involved in the synthesis of the outer-core region of both O-LPS and A-LPS.

  core oligosaccharide, O-antigen polymerase, virulence factor, Porphyromonas gingivalis, A-lipopolysaccharides, A-LPS, O-LPS, A-polysaccharide

  NCBI PubMed ID: 25733619
  Publication DOI: 10.1128/JB.02562-14
  Journal NLM ID: 2985120R
  Publisher: American Society for Microbiology
  Correspondence: m.rangarajan@qmul.ac.uk (Minnie Rangarajan)
  Institutions: Institute of Dentistry, Turner Street, London E1 2AD Centre for Immunology and Infectious Disease, Blizard Institute, 4, Newark Street, London E1 2AT, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, United Kingdom
  Methods: 13C NMR, 1H NMR, methylation, NMR-2D, PCR, GC-MS, SDS-PAGE, DNA techniques, acid hydrolysis, GLC, Western blotting, composition analysis, NMR-1D, methanolysis, GPC
  
   
  
  Porphyromonas gingivalis W50, Porphyromonas gingivalis ∆PG1142
  CSDB ID 30826 (all data & tools)

Show legend Show as text

Structure type: oligomer
Trivial name: anionic lipopolysaccharide (A-LPS)
Compound class: LPS
Contained glycoepitopes: IEDB_115576,IEDB_120354,IEDB_123890,IEDB_130650,IEDB_130695,IEDB_130701,IEDB_136104,IEDB_137778,IEDB_140116,IEDB_141111,IEDB_141181,IEDB_141793,IEDB_141807,IEDB_141828,IEDB_141829,IEDB_141830,IEDB_141831,IEDB_141832,IEDB_143632,IEDB_144983,IEDB_144996,IEDB_151531,IEDB_152206,IEDB_153220,IEDB_153762,IEDB_153763,IEDB_164174,IEDB_164176,IEDB_474450,IEDB_76933,IEDB_857732,IEDB_857735,IEDB_983930,SB_136,SB_191,SB_196,SB_197,SB_198,SB_44,SB_67,SB_72

• Article ID: 6105
  Madej M, Nowakowska Z, Ksiazek M, Lasica AM, Mizgalska D, Nowak M, Jacula A, Bzowska M, Scavenius C, Enghild JJ, Aduse-Opoku J, Curtis MA, Gomis-Rüth FX, Potempa J "PorZ, an Essential Component of the Type IX Secretion System of Porphyromonas gingivalis, Delivers Anionic Lipopolysaccharide to the PorU Sortase for Transpeptidase Processing of T9SS Cargo Proteins" - mBio 12(1) (2021) e02262
  

  Cargo proteins of the type IX secretion system (T9SS) in human pathogens from the Bacteroidetes phylum invariably possess a conserved C-terminal domain (CTD) that functions as a signal for outer membrane (OM) translocation. In Porphyromonas gingivalis, the CTD of cargos is cleaved off after translocation, and anionic lipopolysaccharide (A-LPS) is attached. This transpeptidase reaction anchors secreted proteins to the OM. PorZ, a cell surface-associated protein, is an essential component of the T9SS whose function was previously unknown. We recently solved the crystal structure of PorZ and found that it consists of two β-propeller moieties, followed by a CTD. In this study, we performed structure-based modeling, suggesting that PorZ is a carbohydrate-binding protein. Indeed, we found that recombinant PorZ specifically binds A-LPS in vitro Binding was blocked by monoclonal antibodies that specifically react with a phosphorylated branched mannan in the anionic polysaccharide (A-PS) component of A-LPS, but not with the core oligosaccharide or the lipid A endotoxin. Examination of A-LPS derived from a cohort of mutants producing various truncations of A-PS confirmed that the phosphorylated branched mannan is indeed the PorZ ligand. Moreover, purified recombinant PorZ interacted with the PorU sortase in an A-LPS-dependent manner. This interaction on the cell surface is crucial for the function of the "attachment complex" composed of PorU, PorZ, and the integral OM β-barrel proteins PorV and PorQ, which is involved in posttranslational modification and retention of T9SS cargos on the bacterial surface.IMPORTANCE Bacteria have evolved multiple systems to transport effector proteins to their surface or into the surrounding milieu. These proteins have a wide range of functions, including attachment, motility, nutrient acquisition, and toxicity in the host. Porphyromonas gingivalis, the human pathogen responsible for severe gum diseases (periodontitis), uses a recently characterized type IX secretion system (T9SS) to translocate and anchor secreted virulence effectors to the cell surface. Anchorage is facilitated by sortase, an enzyme that covalently attaches T9SS cargo proteins to a unique anionic lipopolysaccharide (A-LPS) moiety of P. gingivalis Here, we show that the T9SS component PorZ interacts with sortase and specifically binds A-LPS. Binding is mediated by a phosphorylated branched mannan repeat in A-LPS polysaccharide. A-LPS-bound PorZ interacts with sortase with significantly higher affinity, facilitating modification of cargo proteins by the cell surface attachment complex of the T9SS.

  Lipopolysaccharide, secretion, Porphyromonas gingivalis, gingipains, T9SS

  NCBI PubMed ID: 33622730
  Publication DOI: 10.1128/mBio.02262-20
  Journal NLM ID: 101519231
  Publisher: Washington, DC: American Society for Microbiology
  Correspondence: F. Xavier Gomis-Ruth ; Jan Potempa
  Institutions: Department of Microbiology, Faculty of Biochemistry, Biophysics, and Biotechnology, Jagiellonian University, Krakow, Poland, Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA, Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland, Department of Cell Biochemistry, Faculty of Biochemistry, Biophysics, and Biotechnology, Jagiellonian University, Krakow, Poland, Interdisciplinary Nanoscience Center (iNANO) and Department of Molecular Biology, Aarhus University, Aarhus, Denmark, Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, United Kingdom, Proteolysis Lab, Department of Structural Biology, Molecular Biology Institute of Barcelona, Higher Scientific Research Council (CSIC), Barcelona, Catalonia, Spain
  Methods: PCR, SDS-PAGE, anion-exchange chromatography, Western blotting, genetic methods, enzymatic digestion, affinity chromatography, SEC, flow cytometry analysis, fluorescence binding assay
  
   
  
  Porphyromonas gingivalis
  CSDB ID 10901 (all data & tools)