Genomic Characterization of the Taylorella Genus

Abstract

The Taylorella genus comprises two species: Taylorella equigenitalis, which causes contagious equine metritis, and Taylorella asinigenitalis, a closely-related species mainly found in donkeys. We herein report on the first genome sequence of T. asinigenitalis, analyzing and comparing it with the recently-sequenced T. equigenitalis genome. The T. asinigenitalis genome contains a single circular chromosome of 1,638,559 bp with a 38.3% GC content and 1,534 coding sequences (CDS). While 212 CDSs were T. asinigenitalis-specific, 1,322 had orthologs in T. equigenitalis. Two hundred and thirty-four T. equigenitalis CDSs had no orthologs in T. asinigenitalis. Analysis of the basic nutrition metabolism of both Taylorella species showed that malate, glutamate and alpha-ketoglutarate may be their main carbon and energy sources. For both species, we identified four different secretion systems and several proteins potentially involved in binding and colonization of host cells, suggesting a strong potential for interaction with their host. T. equigenitalis seems better-equipped than T. asinigenitalis in terms of virulence since we identified numerous proteins potentially involved in pathogenicity, including hemagluttinin-related proteins, a type IV secretion system, TonB-dependent lactoferrin and transferrin receptors, and YadA and Hep_Hag domains containing proteins. This is the first molecular characterization of Taylorella genus members, and the first molecular identification of factors potentially involved in T. asinigenitalis and T. equigenitalis pathogenicity and host colonization. This study facilitates a genetic understanding of growth phenotypes, animal host preference and pathogenic capacity, paving the way for future functional investigations into this largely unknown genus.

Predicting the Proteins of Angomonas deanei, Strigomonas culicis and Their Respective Endosymbionts Reveals New Aspects of the Trypanosomatidae Family

“…Therefore, the A. deanei and S. culicis symbiont genomes are reduced when compared to Taylorella, which also have reduced genomes when compared to Bordetella or Achromobacter [26], [27]. Alignments indicate the existence of similar sequences between the Taylorella and the kinetoplastid symbionts (Figure 2B and C), corroborating the results obtained in the clustering analyses.…”

“…All these species are phylogenetically related to β-proteobacteria belonging to the Alcaligenaceae family. The genus Taylorella consists of two species, T. equigenitalis and T. asinigenitalis , which are microaerophilic, slow-growing gram-negative bacteria belonging to the family Alcaligenaceae [26], [27]. T. equigenitalis is an intracellular facultative pathogen in horses that causes contagious equine metritis (CEM), a sexually transmitted infection [28].…”

Genome Implosion Elicits Host-Confinement in Alcaligenaceae: Evidence from the Comparative Genomics of Tetrathiobacter kashmirensis, a Pathogen in the Making

“…Except for these few unique elements, the Te genome is essentially a small subset of the consensus Alcaligenaceae genome, and more specifically that of Tk . Most significantly, orthologs of all the Te genes putatively involved in host cell binding and colonization [25] were found to be present in the genome of Tk , or for that matter A8 and Bb . These included genes for (a) O-antigens, (b) proteins containing eukaryotic ankyrin or tetratricopeptide repeat motifs, (c) hemagglutinin-related proteins, (d) RND efflux systems, (e) four secretion systems including T4SS, (f) YadA and Hep_Hag domains containing proteins, (f) TonB-dependent receptors, and (g) the chaperonin GroEL (HSP60 family).…”

“…So it seems quite reasonable to infer that basic calibers for attaching, colonizing and persisting in host tissues could have had an early origin in Alcaligenaceae . Logically, this means facultative asymptomatic commensalism or opportunistic pathogenicity as practised by species of Taylorella [25], [26] or Achromobacter [5], [27] may also be intrinsic to Tk .…”

Genome sequences published outside of Standards in Genomic Sciences, January-March 2012

“…Stenotrophomonas maltophilia RR-10, sequence accession AGRB00000000 [42] Strain HIMB30, sequence accession AGIG00000000 [43] Taylorella equigenitalis, sequence accession CP003059 [44] Vibrio campbellii DS40M4, sequence accession AGIE00000000 [45] Vibrio fischeri SR5, sequence accession AHIH00000000 [46] Yersinia enterocolitica, sequence accession AGQO00000000 [47] Phylum Tenericutes Candidatus Mycoplasma haemominutum, sequence accession HE613254 [48] Mycoplasma haemocanis strain Illinois, sequence accession CP003199 [49] Mycoplasma iowae, sequence accession AGFP00000000 [50] Mycoplasma pneumoniae Type 2a Strain 309, sequence accession AP012303 [51] …”