ena-STUDY-NOTTINGHAM TRENT UNIVERSITY, UK-31-05-2015-21:12:10:344-296
Genetic import and phenotype specific alleles associated with hyperinvasion in Campylobacter jejuni.
Campylobacter jejuni is a major zoonotic pathogen, causing gastroenteritis in humans. Invasion is an important pathogenesis trait by which C. jejuni causes disease. Here we report the whole genome sequence analysis of a group of six isolates which were identified as hyperinvasive using human intestinal cell lines. Phylogenetic analysis based on the genome sequences of these strains showed that the hyperinvasive phenotype is a generalist trait. Despite that these strains are only distantly related based on the whole genome phylogeny, they shared genes within the capsule region with high identity to the capsule genes from C. lari and C. jejuni subsp. doylei. There were genes unique to the hyperinvasive strains with identity to the non-jejuni genes, and had allelic variants of mainly the pathogenesis related genes already known in the other C. jejuni. In particular, the sequence of flagella genes, flgD-E and flgL were highly conserved amongst the hyperinvasive strains and divergent from sequences in the other C. jejuni. A novel cdt operon was also identified as present in all hyperinvasive strains in addition to the classic cdt operon known in all other C. jejuni. Overall, the presence of orthologues of genes from other Campylobacter species in the genome of these strains, notably with in the capsule region, and the statistically significant (p<0.05) association of flagella and secondary cdt genes with hyperinvasion are responsible for the hyperinvasive phenotype of these strains.
Campylobacter jejuni is a major zoonotic pathogen, causing gastroenteritis in humans. Invasion is an important pathogenesis trait by which C. jejuni causes disease. Here we report the whole genome sequence analysis of a group of six isolates which were identified as hyperinvasive using human intestinal cell lines. Phylogenetic analysis based on the genome sequences of these strains showed that the hyperinvasive phenotype is a generalist trait. Despite that these strains are only distantly related based on the whole genome phylogeny, they shared genes within the capsule region with high identity to the capsule genes from C. lari and C. jejuni subsp. doylei. There were genes unique to the hyperinvasive strains with identity to the non-jejuni genes, and had allelic variants of mainly the pathogenesis related genes already known in the other C. jejuni. In particular, the sequence of flagella genes, flgD-E and flgL were highly conserved amongst the hyperinvasive strains and divergent from sequences in the other C. jejuni. A novel cdt operon was also identified as present in all hyperinvasive strains in addition to the classic cdt operon known in all other C. jejuni. Overall, the presence of orthologues of genes from other Campylobacter species in the genome of these strains, notably with in the capsule region, and the statistically significant (p<0.05) association of flagella and secondary cdt genes with hyperinvasion are responsible for the hyperinvasive phenotype of these strains.