Whole genome sequence analysis indicates recent diversification of mammal-associated Campylobacter fetus and implicates a genetic factor associated with H2S production. (December 2016) - van der Graaf–van Bloois, Linda
Abstract Background Campylobacter fetus (C. fetus ) can cause disease in both humans and animals.C. fetus has been divided into three subspecies:C. fetus subsp.fetus (Cff), C. fetus subsp.venerealis (Cfv) andC. fetus subsp.testudinum (Cft). Subspecies identification of mammal-associatedC. fetus strains is crucial in the control of Bovine Genital Campylobacteriosis (BGC), a syndrome associated with Cfv. The prescribed methods for subspecies identification of the Cff and Cfv isolates are: tolerance to 1 % glycine and H2 S production. Results In this study, we observed the deletion of a putative cysteine transporter in the Cfv strains, which are not able to produce H2 S from L-cysteine. Phylogenetic reconstruction of the core genome single nucleotide polymorphisms (SNPs) within Cff and Cfv strains divided these strains into five different clades and showed that the Cfv clade and a Cff clade evolved from a single Cff ancestor. Conclusions MultipleC. fetus clades were observed, which were not consistent with the biochemical differentiation of the strains. This suggests the need for a closer evaluation of the currentC. fetus subspecies differentiation, considering that the phenotypic differentiation is still applied in BGC control programs.