title: Phylogenetic relationships between Toxoplasma and Sarcocystis deduced from a comparison of 18S rDNA sequences.
abstract: The current taxonomy of parasites in the genus Sarcocystis is largely based on morphological characteristics as well as on host specificity and life-cycle structure. Recently, phylogenetic analyses of partial ribosomal RNA (rRNA) sequences provided support for paraphyly of Sarcocystis. We have tested the validity of this hypothesis by sequencing the complete 18S rRNA genes of Sarcocystis arieticanis, Sarcocystis gigantea and Sarcocystis tenella and comparing them with gene sequences derived from other taxa of the phylum Apicomplexa. The results obtained from this study do not reject the hypothesis of monophyly of Sarcocystis species, although the bootstrap data were inconclusive for some species.
authors.affiliation: Department of Cell and Molecular Biology, University of Technology Sydney, Gore Hill, New South Wales, Australia.
authors.forename: T J
authors.initials: TJ
authors.lastname: Ellis
authors.forename: K
authors.initials: K
authors.lastname: Luton
authors.forename: P R
authors.initials: PR
authors.lastname: Baverstock
authors.forename: G
authors.initials: G
authors.lastname: Whitworth
authors.forename: A M
authors.initials: AM
authors.lastname: Tenter
authors.forename: A M
authors.initials: AM
authors.lastname: Johnson
mesh_terms: D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D004275:DNA, Ribosomal / Q000235:genetics*; D016786:Eimeria tenella / Q000145:classification / Q000235:genetics; D017125:Genes, Protozoan / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics*; D012522:Sarcocystis / Q000145:classification* / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014122:Toxoplasma / Q000145:classification* / Q000235:genetics
chemical_list: D004275:DNA, Ribosomal; D012337:RNA, Ribosomal, 18S