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Taylorella equigenitalis is the causative agent of contagious equine metritis (CEM), a sexually transmitted infection of horses. We herein report the genome sequence of T. equigenitalis strain MCE9, isolated in 2005 from the urethral fossa of a 4-year-old stallion in France.Taylorella equigenitalis is a slow-growing microaerophilic Gram-negative coccobacillus, classified in the family Alcaligenaceae (10). It is the causative agent of contagious equine metritis (CEM), a sexually transmitted infection of horses first reported in 1977 (3, 11), and currently has been detected in many countries and various horse breeds. CEM is characterized in infected mares by abundant mucopurulent vaginal discharge and a variable degree of vaginitis, endometritis, and cervicitis that usually result in temporary infertility or early abortion. However, mares may also be asymptomatic (9). Although no clinical signs have been observed in stallions, the infection is most frequently transmitted by carrier stallions, which are the main vector for the infection (4). We report herein the genome sequence of T. equigenitalis MCE9, which was isolated in 2005 from the urethral fossa of a 4-year-old stallion from a stud farm in the Haute-Savoie (France). The strain is currently maintained by the French National Reference Laboratory for CEM (Anses, Dozulé Laboratory for Equine Diseases, Dozulé, France).Whole-genome sequencing was performed by combining the GS FLX (8) and Solexa (2) paired-end sequencing technologies (carried out by Beckman Coulter Genomics, Danvers, MA). Genomic libraries containing 3-kb inserts were constructed, and 410,100 reads (including 50.5% of paired-end reads) were produced using the GS FLX system, giving 71-fold coverage of the genome, and then assembled into five large contigs in one potential large scaffold using the Newbler software program (454 Life Sciences, Branford, CT). A total of 1.5 million reads with an average length of 92 bp were generated using an Illumina Solexa Genome Analyzer II instrument and mapped to the contigs using the Consed graphical software tool (5) in order to correct eventual error generated by the 454 technology. The order and orientation of the five large contigs were confirmed by PCR and assembled into a single sequence. Annotation resulted from merging the results obtained from the RAST (Rapid Annotation using Subsystem Technology) server (1), tRNAscan-SE-1.21 (7), and RNAmmer-1.2 (6), followed by manual curation.The T. equigenitalis MCE9 genome is 1,695,860 bp long with an overall GϩC content of 37.42%. There was no evidence of plasmids. There were 1,556 protein-coding genes, with an average length of 1,007 bp. Of these, 1,231 (Ϸ79%) were assigned a predicted function. There are 38 tRNA genes for all amino acids and three copies of the 16S-23S-5S rRNA operon, three putative transposase genes, and four putative phagerelated genes. This is the first genome sequence of the Taylorella genus (which also contains the donkey-related Taylorella asinigenitalis species), and its availability will ...

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.

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Equine herpesviruses type 1 and 4 (EHV-1 and EHV-4) are ubiquitous in the equine population. One of their main properties is their ability to establish life-long latent infections in their hosts even in those with natural or vaccine-induced immunity. However, effect of vaccination status on prevalence and tissue tropism was not established. In this study, EHV-1 and EHV-4 were detected by polymerase chain reaction and by classical virus isolation from neural, epithelial and lymphoid tissues collected from unvaccinated (33) or vaccinated (23) horses. The percentage of EHV-1- and EHV-4-positive horses between vaccinates and unvaccinates was similar. Both viruses were detected in all tissues of both groups; in particular, lymph nodes draining the respiratory tract, nasal epithelium and nervous ganglia [i.e. trigeminal ganglia (TG)], which represent the main positive sites for EHV-1 and EHV-4. In vaccinated animals, the nervous ganglia (i.e. TG) were less frequently positive than in unvaccinated animals. Detection of positive TG was strongly correlated to the presence of EHV-1 in nasal epithelium.