The complete mitochondrial genome of Caryospora bigenetica (Eimeriidae, Eucoccidiorida, Coccidiasina, Apicomplexa)

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

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.

A linear mitochondrial genome of Cyclospora cayetanensis (Eimeriidae, Eucoccidiorida, Coccidiasina, Apicomplexa) suggests the ancestral start position within mitochondrial genomes of eimeriid coccidia

The near complete mitochondrial genome for Cyclospora cayetanensis is 6184 bp in length with three protein-coding genes (Cox1, Cox3, CytB) and numerous lsrDNA and ssrDNA fragments. Gene arrangements were conserved with other coccidia in the Eimeriidae, but the C. cayetanensis mitochondrial genome is not circular-mapping. Terminal transferase tailing and nested PCR completed the 5'-terminus of the genome starting with a 21 bp A/T-only region that forms a potential stem-loop. Regions homologous to the C. cayetanensis mitochondrial genome 5'-terminus are found in all eimeriid mitochondrial genomes available and suggest this may be the ancestral start of eimeriid mitochondrial genomes.