Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Enterobacter cloacae [ICD11:
XN3YM 
]
The structure was elucidated in this paperPublication DOI: 10.1016/j.carres.2016.03.008Journal NLM ID: 0043535Publisher: Elsevier
Correspondence: perepel

ioc.ac.ru
Institutions: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China
The O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Enterobacter cloacae G3421 and studied by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy. In addition, partial solvolysis with anhydrous trifluoroacetic acid was applied, which cleaved selectively the α-l-rhamnopyranosidic linkages. The following structure of the branched hexasaccharide repeating unit was established. [Formula: see text]. The O-polysaccharide studied shares the β-l-Rhap-(1→4)-α-l-Rhap-(1→2)-α-l-Rhap trisaccharide fragment with the O-polysaccharide of Shigella boydii type 18. The O-antigen gene cluster of E. cloacae G3421 was sequenced. Functions of genes in the cluster, including those for glycosyltransferases, were tentatively assigned by a comparison with sequences in the available databases and found to be consistent with the O-polysaccharide structure.
Lipopolysaccharide, bacterial polysaccharide structure, O-antigen gene cluster, Enterobacter cloacae, Solvolytic cleavage
Structure type: oligomer
Location inside paper: abstract, p.57, chart 1, oligosaccharide 2
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_136906,IEDB_137472,IEDB_141794,IEDB_142488,IEDB_144998,IEDB_146664,IEDB_151528,IEDB_190606,IEDB_225177,IEDB_885823,IEDB_983931,SB_192,SB_7
Methods: 13C NMR, 1H NMR, NMR-2D, PCR, DNA sequencing, sugar analysis, ESI-MS, acid hydrolysis, GLC, NMR-1D, GPC, function analysis of gene clusters, solvolysis with trifluoroacetic acid
Comments, role: Partial cleavage of the OPS by solvolysis with anhydrous CF3CO2H.
Related record ID(s): 11286, 11662
NCBI Taxonomy refs (TaxIDs): 550Reference(s) to other database(s): GTC:G97484LE
Show glycosyltransferases
NMR conditions: in D2O at 303 K
[as TSV]
13C NMR data:
Linkage Residue C1 C2 C3 C4 C5 C6
3 aDGlcp 96.4 69.5 70.9 70.6 72.5 62.2
4,3,3 aDGalp 100.1 73.9 74.2 70.8 73.8 61.8
4,3,2 Ac ? 23.5
4,3 aDFucpN 95.9 49.5 74.1 68.5 68.1 16.8
4 bLRhap 102.0 68.5 78.9 71.6 73.6 18.2
xLRha-ol 63.8 72.4 78.4 83.4 67.8 20.1
1H NMR data:
Linkage Residue H1 H2 H3 H4 H5 H6
3 aDGlcp 5.14 3.82 3.77 4.01 3.88 3.76-3.76
4,3,3 aDGalp 5.17 3.58 3.73 3.45 3.85 3.76-3.85
4,3,2 Ac - 2.07
4,3 aDFucpN 5.02 4.39 4.10 4.09 4.35 1.24
4 bLRhap 4.79 4.21 3.65 3.46 3.46 1.36
xLRha-ol 3.85-3.89 4.07 4.09 3.88 4.08 1.28
1H/13C HSQC data:
Linkage Residue C1/H1 C2/H2 C3/H3 C4/H4 C5/H5 C6/H6
3 aDGlcp 96.4/5.14 69.5/3.82 70.9/3.77 70.6/4.01 72.5/3.88 62.2/3.76-3.76
4,3,3 aDGalp 100.1/5.17 73.9/3.58 74.2/3.73 70.8/3.45 73.8/3.85 61.8/3.76-3.85
4,3,2 Ac 23.5/2.07
4,3 aDFucpN 95.9/5.02 49.5/4.39 74.1/4.10 68.5/4.09 68.1/4.35 16.8/1.24
4 bLRhap 102.0/4.79 68.5/4.21 78.9/3.65 71.6/3.46 73.6/3.46 18.2/1.36
xLRha-ol 63.8/3.85-3.89 72.4/4.07 78.4/4.09 83.4/3.88 67.8/4.08 20.1/1.28
1H NMR data:
| Linkage | Residue | H1 | H2 | H3 | H4 | H5 | H6 |
| 3 | aDGlcp | 5.14 | 3.82 | 3.77 | 4.01 | 3.88 | 3.76 3.76 |
| 4,3,3 | aDGalp | 5.17 | 3.58 | 3.73 | 3.45 | 3.85 | 3.76 3.85 |
| 4,3,2 | Ac |
| 2.07 | |
| 4,3 | aDFucpN | 5.02 | 4.39 | 4.10 | 4.09 | 4.35 | 1.24 |
| 4 | bLRhap | 4.79 | 4.21 | 3.65 | 3.46 | 3.46 | 1.36 |
| | xLRha-ol | 3.85 3.89 | 4.07 | 4.09 | 3.88 | 4.08 | 1.28 |
|
13C NMR data:
| Linkage | Residue | C1 | C2 | C3 | C4 | C5 | C6 |
| 3 | aDGlcp | 96.4 | 69.5 | 70.9 | 70.6 | 72.5 | 62.2 |
| 4,3,3 | aDGalp | 100.1 | 73.9 | 74.2 | 70.8 | 73.8 | 61.8 |
| 4,3,2 | Ac | ? | 23.5 | |
| 4,3 | aDFucpN | 95.9 | 49.5 | 74.1 | 68.5 | 68.1 | 16.8 |
| 4 | bLRhap | 102.0 | 68.5 | 78.9 | 71.6 | 73.6 | 18.2 |
| | xLRha-ol | 63.8 | 72.4 | 78.4 | 83.4 | 67.8 | 20.1 |
|
 The spectrum also has 1 signal at unknown position (not plotted). |
There is only one chemically distinct structure: