Michel Gilbert

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Ganglioside mimicry by Campylobacter jejuni lipo-oligosaccharide (LOS) is thought to be a critical factor in the triggering of the Guillain-Barré and Miller-Fisher syndrome neuropathies after C. jejuni infection. The combination of a completed genome sequence and a ganglioside GM1-like LOS structure makes C. jejuni NCTC 11168 a useful model strain for the(More)
The genes encoding the alpha-2,3-sialyltransferases involved in lipooligosaccharide biosynthesis from Neisseria meningitidis and Neisseria gonorrhoeae have been cloned and expressed in Escherichia coli. A high sensitivity enzyme assay using a synthetic fluorescent glycosyltransferase acceptor and capillary electrophoresis was used to screen a genomic(More)
We have compared the lipo-oligosaccharide (LOS) biosynthesis loci from 11 Campylobacter jejuni strains expressing a total of 8 different ganglioside mimics in their LOS outer cores. Based on the organization of the genes, the 11 corresponding loci could be classified into three classes, with one of them being clearly an intermediate evolutionary step(More)
Molecular mimicry of Campylobacter jejuni lipo-oligosaccharides (LOS) with gangliosides in nervous tissue is considered to induce cross-reactive antibodies that lead to Guillain-Barre syndrome (GBS), an acute polyneuropathy. To determine whether specific bacterial genes are crucial for the biosynthesis of ganglioside-like structures and the induction of(More)
OBJECTIVE To assess the production mechanism of anti-GQ1b autoantibody in Fisher syndrome (FS). METHODS The authors conducted a prospective case-control serologic study of five antecedent infections (Campylobacter jejuni, cytomegalovirus, Epstein-Barr virus, Mycoplasma pneumoniae, and Haemophilus influenzae) in 73 patients with FS and 73 sex- and(More)
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-Barré syndrome. We first cloned a gene encoding an alpha-2, 3-sialyltransferase (cst-I) using an activity(More)
We recently demonstrated that Campylobacter jejuni produces a capsular polysaccharide (CPS) that is the major antigenic component of the classical Penner serotyping system distinguishing Campylobacter into >60 groups. Although the wide variety of C. jejuni serotypes are suggestive of structural differences in CPS, the genetic mechanisms of such differences(More)
The lipopolysaccharide (LPS) of non-typeable Haemophilus influenzae (NTHi) can be substituted at various positions by N-acetylneuraminic acid (Neu5Ac). LPS sialylation plays an important role in pathogenesis. The only LPS sialyltransferase characterized biochemically to date in H. influenzae is Lic3A, an alpha-2,3-sialyltransferase responsible for the(More)
Campylobacter jejuni strains exhibit significant variation in the genetic content of the lipooligosaccharide (LOS) biosynthesis loci with concomitant differences in LOS structure. The C. jejuni LOS loci have been grouped into six classes based on gene content and organization. Utilizing PCR amplifications of genes from these loci, we were able to classify a(More)
Sialic acid terminates oligosaccharide chains on mammalian and microbial cell surfaces, playing critical roles in recognition and adherence. The enzymes that transfer the sialic acid moiety from cytidine-5'-monophospho-N-acetyl-neuraminic acid (CMP-NeuAc) to the terminal positions of these key glycoconjugates are known as sialyltransferases. Despite their(More)