title: Mitochondrial genome of Babesia orientalis, apicomplexan parasite of water buffalo (Bubalus babalis, Linnaeus, 1758) endemic in China.
abstract: BACKGROUND
  Apicomplexan parasites of the genus Babesia, Theileria and Plasmodium are very closely related organisms. Interestingly, their mitochondrial (mt) genomes are highly divergent. Among Babesia, Babesia orientalis is a new species recently identified and specifically epidemic to the southern part of China, causing severe disease to water buffalo. However, no information on the mt genome of B. orientalis was available.
  
  
  METHODS
  Four pairs of primers were designed based on the full genome sequence of B. orientalis (unpublished data) and by aligning reported mt genomes of B. bovis, B. bigemina, and T. parva. The entire mt genome was amplified by four sets of PCR. The obtained mt genome was annotated by aligning with published apicomplexan mt genomes and Artemis software v11. Phylogenetic analysis was performed by using cox1 and cob amino acid sequences.
  
  
  RESULTS
  The complete mt genome of B. orientalis (Wuhan strain) was sequenced and characterized. The entire mt genome is 5996 bp in length with a linear form, containing three protein-coding genes including cytochrome c oxidase I (cox1), cytochrome b (cob) and cytochrome c oxidase III (cox3) and six rRNA large subunit gene fragments. The gene arrangement in B. orientalis mt genome is similar to those of B. bovis, B. gibsoni and Theileria parva, but different from those of T. orientalis, T. equi and Plasmodium falciparum. Comparative analysis indicated that cox1 and cob genes were more conserved than cox3. Phylogenetic analysis based on amino acid sequences of cox1, cob and cox1 + cob, respectively, revealed that B. orientalis fell into Babesia clade with the closest relationship to B. bovis.
  
  
  CONCLUSIONS
  The availability of the entire mt genome sequences of B. orientalis provides valuable information for future phylogenetic, population genetics and molecular epidemiological studies of apicomplexan parasites.
authors.forename: Lan
authors.initials: L
authors.lastname: He
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Qing-Li
authors.initials: QL
authors.lastname: Zhang
authors.forename: Wen-Jie
authors.initials: WJ
authors.lastname: Zhang
authors.forename: Hui-Hui
authors.initials: HH
authors.lastname: Feng
authors.forename: Muhammad Kasib
authors.initials: MK
authors.lastname: Khan
authors.forename: Min
authors.initials: M
authors.lastname: Hu
authors.forename: Yan-Qin
authors.initials: YQ
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, China. zhaojunlong@mail.hzau.edu.cn.
authors.forename: Jun-Long
authors.initials: JL
authors.lastname: Zhao
mesh_terms: D000818:Animals; D001403:Babesia / Q000235:genetics* / Q000302:isolation & purification; D001404:Babesiosis / Q000469:parasitology*; D001483:Base Sequence; D002020:Buffaloes / Q000469:parasitology*; D002681:China; D017931:DNA Primers / Q000235:genetics; D016054:DNA, Protozoan / Q000235:genetics; D054629:Genome, Mitochondrial / Q000235:genetics*; D018503:Genome, Protozoan / Q000235:genetics*; D058977:Molecular Sequence Annotation; D008969:Molecular Sequence Data; D010802:Phylogeny; D015800:Protozoan Proteins / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D016054:DNA, Protozoan; D015800:Protozoan Proteins