The complete mitochondrial genome sequence of Eimeria leuckarti (Eimeriidae, Coccidia, Apicomplexa) infecting domestic horses (Equus ferus caballus)

Abstract

The complete mitochondrial genome of Eimeria leuckarti (Eimeriidae, Coccidia, Apicomplexa) was obtained. This morphologically distinctive coccidium is considered to be the only valid Eimeria species of equids and it infects a range of both domestic and wild horses and their relatives. Despite the distinctive appearance of the oocysts of E. leuckarti, the mitochondrial genome organization and gene contents were comparable to other Eimeria spp. and related eimeriid coccidia infecting a range of mammals and birds. The greatly reduced 6242 bp genome is circular-mapping and contains three protein-coding genes (COI, COIII, CytB), 18 fragments encoding the large subunit rRNA (LSU), and 13 fragments encoding the small subunit (SSU) rRNA. No tRNA was encoded similar to other Apicomplexa. A Bayesian inference tree based on aligned CDS and rDNA fragments from Eimeria leuckarti and 34 other coccidia demonstrated that this mt genome has close phylogenetic affinities to Eimeria and Isospora species, and related eimeriid coccidia.

Keywords:

• Coccidian parasite
• Apicomplexa
• mitochondrial genome
• fragmented rRNA
• equine host

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Data availability statement

The genome sequence data are openly available in GenBank of NCBI at [https://www.ncbi.nlm.nih.gov] under accession no. MW354691, and additional data that support the findings of this study are available at Mendeley Data at http://dx.doi.org/10.17632/j6tjg4sdjf.2.

Additional information

Funding

This research was supported by a Discovery Grant [DG400566] to JRB from the Natural Sciences and Engineering Research Council of Canada (NSERC). EER was supported by a OVC PhD Scholarship from the Ontario Veterinary College, University of Guelph.