Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Host organism: Homo sapiens
Associated disease: gastric mucosa [ICD11:
XA0PT3 
];
infection due to Helicobacter pylori [ICD11:
XN3DY 
]
The structure was elucidated in this paperNCBI PubMed ID: 20227685Publication DOI: 10.1016/j.carres.2010.01.022Journal NLM ID: 0043535Publisher: Elsevier
Correspondence: mac

ua.pt
Institutions: Departamento de Química, Universidade de Aveiro, Aveiro, Portugal, LEPAE, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal, Centro de Engenharia Biológica, Universidade do Minho, Campus de Gualtar, Braga, Portugal, Institute of Molecular Pathology and Immunology, University of Porto, Portugal, Medical Faculty of Porto, Porto, Portugal, CICECO, University of Aveiro, Aveiro, Portugal, Department of Chemistry, University of Guelph, Guelph, ON, Canada
With the intent of contributing to a carbohydrate-based vaccine against the gastroduodenal pathogen, Helicobacter pylori, we report here the structure of cell-surface mannans obtained from a virulent strain. Unlike other wild-type strains, this strain was found to express in good quantities this polysaccharide in vitro. Structural analysis revealed a branched mannan formed by a backbone of α-(1→6)-linked mannopyranosyl residues with approximately 80% branching at the O-2 position. The branches were composed of O-2-linked Man residues in both α- and β-configurations: [abstract: see text]. In addition, this strain also expressed cell-surface emblematic H. pylori lipopolysaccharides (LPS) containing partially fucosylated polyLacNAc O-chains. Affinity assays with polymyxin-B and concanavalin A revealed no association between the mannan and the LPS. The described mannans may be implicated in the mediation of host-microbial interactions and immunological modulation.
Lipopolysaccharide, Helicobacter pylori, vaccine, mannan, cell-surface glycans
Structure type: polymer chemical repeating unit
Location inside paper: abstract, p.832
Trivial name: i-antigen, N-acetyllactosaminoglycan, poly-(N-acetyl-b-lactosamine) chain, polylacNAc O-chain, poly(N-acetyl-b-lactosamine) chain, Poly LacNAc
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_130646,IEDB_130655,IEDB_130697,IEDB_135813,IEDB_136044,IEDB_137340,IEDB_137472,IEDB_137776,IEDB_140108,IEDB_140122,IEDB_141794,IEDB_141807,IEDB_150939,IEDB_151531,IEDB_158550,IEDB_190606,SB_165,SB_166,SB_173,SB_187,SB_195,SB_30,SB_7,SB_88
Methods: 13C NMR, 1H NMR, NMR-2D, 31P NMR, composition analysis, affinity chromatography
Comments, role: O-chains contains 3.4% of terminal Fuc and 4.0% of O-3,4-linked GlcNAc
Related record ID(s): 288, 3527, 3588, 6391, 21870, 25245, 25599
NCBI Taxonomy refs (TaxIDs): 210Reference(s) to other database(s): GTC:G39453SO, GlycomeDB:
15913
Show glycosyltransferases
NMR conditions: in D2O at 310 K
[as TSV]
13C NMR data:
Linkage Residue C1 C2 C3 C4 C5 C6
4 bDGalp 103.03 ? ? ? ? ?
2 Ac
bDGlcpN 102.56 ? ? ? ? ?
1H NMR data:
Linkage Residue H1 H2 H3 H4 H5 H6
4 bDGalp 4.45 3.52 3.68 ? ? ?
2 Ac
bDGlcpN 4.65 3.84 ? ? ? ?
1H/13C HSQC data:
Linkage Residue C1/H1 C2/H2 C3/H3 C4/H4 C5/H5 C6/H6
4 bDGalp 103.03/4.45 ?/3.52 ?/3.68 ?/? ?/? ?/?
2 Ac
bDGlcpN 102.56/4.65 ?/3.84 ?/? ?/? ?/? ?/?
1H NMR data:
| Linkage | Residue | H1 | H2 | H3 | H4 | H5 | H6 |
| 4 | bDGalp | 4.45 | 3.52 | 3.68 | ? | ? | ? |
| 2 | Ac | |
| | bDGlcpN | 4.65 | 3.84 | ? | ? | ? | ? |
|
13C NMR data:
| Linkage | Residue | C1 | C2 | C3 | C4 | C5 | C6 |
| 4 | bDGalp | 103.03 | ? | ? | ? | ? | ? |
| 2 | Ac | |
| | bDGlcpN | 102.56 | ? | ? | ? | ? | ? |
|
 The spectrum also has 10 signals at unknown positions (not plotted). |
There is only one chemically distinct structure: