NGS-based phylogeny of diphtheria-related pathogenicity factors in different Corynebacterium spp. implies species-specific virulence transmission

• DOI: 10.1186/s12866-019-1402-1
• Publication Date: 2019-02-01T13:03:18Z
• Authors: Alexandra Dangel; Anja Berger; Regina Konrad; Andreas Sing
• Keywords: Parasitology; Corynebacterium diphtheriae; Corynebacterium; Medical microbiology; Mycology

Diphtheria toxin (DT) is produced by toxigenic strains of the human pathogen Corynebacterium diphtheriae as well zoonotic C. ulcerans and pseudotuberculosis. Toxigenic may cause severe respiratory diphtheria, myocarditis, neurological damage or cutaneous diphtheria. The DT encoding tox gene located in a mobile genomic region variability between has been postulated based on sequences few isolates. In contrast, species-specific sequence analysis diphtheria repressor (dtxR), occurring both non-toxigenic species, not done yet. We used whole genome sequencing data from 91 46 isolates different pathogenic species animal origin to elucidate differences extracted DT, DtxR tox-surrounding genetic elements phylogenetic large sample set.Sequences DtxR, data, could be classified four distinct, nearly clades, corresponding diphtheriae, pseudotuberculosis, atypical gene-bearing wildlife cluster. Average amino acid similarities were above 99% for within groups, but lower them. For subgroups below level identified, correlating with tox-comprising elements. most genes known prophages. diverse tox-including identified: either prophages differing an alternative pathogenicity island (PAI) described previously. One isolate showed different, shorter putative PAI. Beyond tox-overlapping elements, harbored variety additional prophages.Our NGS 137 indicate existence backgrounds DT-mediated evolution once acquired features strains. Different groups pathogenicity-related imply that transmission pathways differ contribute their emerging potential.