Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Host organism: Homo sapiens
Associated disease: melioidosis [ICD11:
1C42 
, ICD11:
XN3LD ];
infection due to Burkholderia pseudomallei [ICD11:
XN3LD ]
The structure was elucidated in this paperNCBI PubMed ID: 29024844Publication DOI: 10.1016/j.carres.2017.09.011Journal NLM ID: 0043535Publisher: Elsevier
Correspondence: mbayliss
dstl.gov.uk; rob.field
jic.ac.uk
Institutions: Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire, SP4 0JQ, UK, Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK, Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK, London School of Hygiene and Tropical Medicine, Keppler Street, London, WC1 7HT, UK
Burkholderia pseudomallei and its close relative B. mallei are human pathogens that are classified as Tier 1 bio-threat agents. Both organisms have previously been shown to constitutively produce a capsular polysaccharide (CPS) that is both a virulence determinant and protective antigen. Extraction and purification of CPS for use as a potential vaccine candidate requires containment level 3 laboratories which is expensive and time-consuming. B. thailandensis strain E555 is closely related to B. pseudomallei and B. mallei, but is non-pathogenic to humans and based on immunological cross-reactivity has previously been shown to express a B. pseudomallei-like CPS. In this study, capsular polysaccharide isolated from an O-antigen deficient strain of B. thailandensis E555 was identified by 1H and 13C NMR spectroscopy as -3-)-2-O-acetyl-6-deoxy-β-d-manno-heptopyranose-(-1, and identical to that produced by B. pseudomallei. This was further substantiated by anti-CPS monoclonal antibody binding. In connection with the production of CPS fragments for use in glycoconjugate vaccines, we set out to assess the importance or otherwise of the CPS 2-OAc groups in immune protection. To this end conjugates of the native and de-O-acetylated CPS with the Hc fragment of tetanus toxin (TetHc) were used as vaccines in a mouse model of melioidosis. The level of protection provided by deacetylated CPS was significantly lower than that from native, acetylated CPS. In addition, sera from mice vaccinated with the deacetylated CPS conjugate did not recognise native CPS. This suggests that CPS extracted from B. thailandensis can be used as antigen and that the acetyl group is essential for protection.
capsular polysaccharide, Burkholderia pseudomallei, melioidosis, glycoconjugate vaccine, Burkholderia thailandensis
Structure type: homopolymer
Location inside paper: abstarct, p.18
Trivial name: 6-deoxy-heptan CPS
Compound class: CPS, O-polysaccharide, O-antigen
Methods: 13C NMR, 1H NMR, SDS-PAGE, sugar analysis, ELISA, acid hydrolysis, Western blotting, biological assays, de-O-acetylation, HPAEC-PAD, antibody binding, conjugation
NCBI Taxonomy refs (TaxIDs): 869728,
884204,
28450Reference(s) to other database(s): GTC:G09650IH, GlycomeDB:
3383
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
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