Research Areas: MicrobiologyThe pathogenesis mechanisms of Campylobacter fetus subsp. venerealis (Cfv), the etiologic
agent of Bovine Genital Campylobacteriosis remain elusive. This study evaluated the virulence
potential and biovar characteristics of Cfv isolates (n = 13) by PCR screening of putative virulencefactor (VF) genes, Multilocus Sequence Typing (MLST) analysis, antimicrobial susceptibility to
tetracycline, penicillin, enrofloxacin and streptomycin testing and whole-genome sequencing (WGS;
n = 5), also comparing the latter with 26 other whole-genome sequences of Cfv strains. The putative
VF genes encoding type IV secretion system of Cfv (virB2-virB11/virD4) were absent in 92% of isolates,
including isolates from aborted foetuses, evidencing that these VF genes are not essential for Cfv
pathogenicity. The parA gene, used as a Cfv diagnostic molecular target, was detected in only 3 of
13 isolates, invalidating its use for diagnosis purposes. Three novel sequence types were identified
by MLST. Although no in vitro antimicrobial resistance was detected, WGS identified antimicrobial
resistance-related genes, including those encoding the multidrug efflux pumps CmeABC and YkkCD,
indicating that their presence is not enough to provide antimicrobial resistance. The SNP and
accessory protein families analysis segregated the Cfv and Cfv biovar intermedius (Cfvi) strains into
different clusters. In conclusion, this study evidenced virulence potential and biovar characteristics
of Cfv and Cfvi, which are of relevance for the control of Bovine Genital Campylobacteriosis.info:eu-repo/semantics/publishedVersio