Comparative Genomics and Pathogenicity Islands of Corynebacterium diphtheriae, Corynebacterium ulcerans, and Corynebacterium pseudotuberculosis

Abstract

The systematic application of next-generation DNA sequencing technologies has provided detailed insights into the genomics of corynebacteria. The genomes of 13 Corynebacterium diphtheriae strains isolated from cases of classical diphtheria, endocarditis and pneumonia were completely sequenced and annotated, providing first insights into the pan-genome of this species. Comparative gene content analyses revealed an enormous collection of variable pilus gene clusters relevant for adhesion properties of C. diphtheriae. Variation in the distributed genome is apparently a common strategy of C. diphtheriae to establish differences in host-pathogen interactions. Molecular data deduced from the complete genome sequences of two Corynebacterium ulcerans strains provided considerable knowledge of candidate virulence factors, including a novel type of ribosome-binding protein with striking structural similarity to Shiga-like toxins. Likewise, functional data deduced from the complete genome sequences of six Corynebacterium pseudotuberculosis isolates from various sources greatly extended the knowledge of virulence factors and indicated that this species is equipped with a distinct gene set promoting its survival under unfavorable environmental conditions encountered in the mammalian host.

Ongoing diphtheria outbreak in Yemen: a cross-sectional and genomic epidemiology study

“…We screened the genomic sequences for the presence of putative pathogenicity associated genes. 23 Sublineage A isolates possessed genes iusABC encoding for an ABCtype iron uptake system, the chtAB genes that are homologous to htaAB genes for haemin binding, a pathogenicity island of C diphtheriae called PICD11, 23 comprising a putative collagenbinding protein, and the spaABC-strA and spaDEF-strBC fimbriae gene clusters (figure 3, appendix 2 p 17). In contrast to sublineage A, most other Yemen isolates did not have the aforementioned gene clusters; their genomes comprised genes sidBA-ddpABC for putative siderophore biosynthesis, irp1ABCD for a putative ABCtype iron transporter, and the irp2ABCDEFGHI and irp2JKLMN operons.…”

Epidemiological, clinical and genomic insights into the ongoing diphtheria outbreak in Yemen

“…We screened the genomic sequences for the presence of putative pathogenicity-associated genes. Sublineage A isolates possessed genes iusABC coding for an ABC-type iron uptake system, the chtAB genes that are homologous to htaAB genes for hemin binding, a pathogenicity island of C. diphtheriae called PICD-11 [27] comprising a putative collagen binding protein suggested to be associated with cutaneous or invasive infections [28], and the spaABC-strA and spaDEF-strBC gene clusters coding for two distinct types of fimbriae ( Figure 3 ). In contrast to sublineage A, most other Yemen isolates did not harbor the above gene clusters.…”

Corynebacterium diphtheriae Proteome Adaptation to Cell Culture Medium and Serum

“…Pathogenic islands (PAI) in pathogenic bacteria include disease- related factors which serves for antibiotic resistance, or proteins which are helpful for the current growth environment [ 80 ]. Twenty-four PAIs are reported in the genome of C. diphtheriae NCTC13129 [ 81 ]. Three proteins of a PAI, including one protein of a putative two component system response regulator (DIP0600) and two proteins involved in siderophore biosynthesis and transport (DIP0585 and DIP0597), were found in bacteria grown in RPMI 1640 and serum and not in bacteria grown in BHI.…”