Multilocus Sequence Typing of Pathogenic Treponemes Isolated from Cloven-Hoofed Animals and Comparison to Treponemes Isolated from Humans

• DOI: 10.1128/aem.00025-16
• Publication Date: 2016-05-23T17:00:57Z
• Authors: Simon R. Clegg; Stuart D. Carter; Richard J. Birtles; Jennifer M. Brown; C. Anthony Hart; Nicholas J. Evans
• Keywords: Phylotype; Multilocus sequence typing; Housekeeping gene

ABSTRACT Treponema species are implicated in many diseases of humans and animals. Digital dermatitis (DD) treponemes reported to cause severe lesions cattle, sheep, pigs, goats, wild elk, causing substantial global animal welfare issues economic losses. The fastidiousness these spirochetes has previously precluded studies investigating within-phylogroup genetic diversity. An archive that we isolated enabled multilocus sequence typing quantify the diversity population structure DD treponemes. Isolates ( n = 121) were obtained from different hosts nine countries on three continents. analyses herein currently at seven housekeeping gene loci confirm classification designated phylogroups: medium , phagedenis pedis phylogroups. Sequence analysis treponeme genes revealed a generally low level among strains within each phylogroup, removing need for used “-like” suffix. Surprisingly, all isolates phylogroup clustered together, regardless host or geographic origin, suggesting same types (STs) can infect Some STs derived multiple animals farm, highlighting probable within-farm transmissions. Several infected similar regions, identifying frequent between-host Interestingly, T. appears be evolving more quickly than by forming two unique ST complexes. lack phylogenetic discrimination between regions substantially contrasts with data other clinically relevant spirochetes. IMPORTANCE recent expansion range digital cattle coupled high 16S rRNA similarity across human treponemes, suggests bacterial disease hosts. This (MLST) study further demonstrates bacteria indeed very similar, raising potential cross-species transmission. also shows infection spread occurs frequently, both locally globally, transmission routes animal-animal alone. These results indicate on-farm biosecurity is important controlling domesticated species. Continued surveillance vigilance ascertaining evolution tracking any pathogens.