Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Campylobacter jejuni [ICD11:
XN4Q5 
]
NCBI PubMed ID: 10660542Publication DOI: 10.1074/jbc.275.6.3896Journal NLM ID: 2985121RPublisher: Baltimore, MD: American Society for Biochemistry and Molecular Biology
Correspondence: warren.wakarchuk
nrc.ca
Institutions: Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada.
We have applied two strategies for the cloning of four genes responsible for the biosynthesis of the GT1a ganglioside mimic in the lipooligosaccharide (LOS) of a bacterial pathogen, Campylobacter jejuni OH4384, which has been associated with Guillain-Barre syndrome. We first cloned a gene encoding an α-2, 3-sialyltransferase (cst-I) using an activity screening strategy. We then used nucleotide sequence information from the recently completed sequence from C. jejuni NCTC11168 to amplify a region involved in LOS biosynthesis from C. jejuni OH4384. The LOS biosynthesis locus from C. jejuni OH4384 is 11.47 kilobase pairs and encodes 13 partial or complete open reading frames, while the corresponding locus in C. jejuni NCTC11168 spans 13.49 kilobase pairs and contains 15 open reading frames, indicating a different organization between these two strains. Potential glycosyltransferase genes were cloned individually, expressed in Escherichia coli, and assayed using synthetic fluorescent oligosaccharides as acceptors. We identified genes encoding a β-1,4-N-acetylgalactosaminyl-transferase (cgtA), a β-1,3-galactosyltransferase (cgtB), and a bifunctional sialyltransferase (cst-II), which transfers sialic acid to O-3 of galactose and to O-8 of a sialic acid that is linked α-2,3- to a galactose. The linkage specificity of each identified glycosyltransferase was confirmed by NMR analysis at 600 MHz on nanomole amounts of model compounds synthesized in vitro. Using a gradient inverse broadband nano-NMR probe, sequence information could be obtained by detection of (3)J(C,H) correlations across the glycosidic bond. The role of cgtA and cst-II in the synthesis of the GT1a mimic in C. jejuni OH4384 were confirmed by comparing their sequence and activity with corresponding homologues in two related C. jejuni strains that express shorter ganglioside mimics in their LOS.
Lipooligosaccharide, gene, Campylobacter jejuni, ganglioside, sialyltransferase, glycosyltransferase, NMR analysis, enzymatic synthesis
Structure type: oligomer
Location inside paper: fig. 1A
Aglycon: inner core
Compound class: LOS
Contained glycoepitopes: IEDB_130648,IEDB_134627,IEDB_136044,IEDB_136794,IEDB_137472,IEDB_137473,IEDB_141794,IEDB_146100,IEDB_147450,IEDB_147451,IEDB_149174,IEDB_150933,IEDB_190606,SB_116,SB_165,SB_166,SB_170,SB_171,SB_172,SB_187,SB_195,SB_23,SB_24,SB_25,SB_39,SB_68,SB_7,SB_70,SB_8,SB_84,SB_88,SB_96,SB_97
Methods: NMR-2D
Biosynthesis and genetic data: biochemical data, genetic data
Related record ID(s): 590, 591
NCBI Taxonomy refs (TaxIDs): 197
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
report error