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United States Department of Agriculture

Agricultural Research Service

Research Project: EPIDEMIOLOGY AND CONTROL OF NEOSPORA CANINUM AND RELATED PROTOZOA Title: Molecular phylogenetic analysis in Hammondia-like organisms based on partial Hsp70 coding sequences

Authors
item Monteiro, R - SAO PAULO BRAZIL
item Richtzenhain, L - SAO PAULO BRAZIL
item Pena S, L - SAO PAULO BRAZIL
item Souza, S - SAO PAULO BRAZIL
item Funada, M - SAO PAULO BRAZIL
item Gennari, S - SAO PAULO BRAZIL
item Dubey, Jitender
item Sreekumar, C - USDA,ARS,ANRI,APDL
item Keid, L - SAO PAULO BRAZIL
item Soares, R - SAO PAULO BRAZIL

Submitted to: Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 2007
Publication Date: August 1, 2007
Citation: Monteiro, R.M., Richtzenhain, L.J., Pena S, L.P., Souza, S.L., Funada, M.R., Gennari, S.M., Dubey, J.P., Sreekumar, C., Keid, L.B., Soares, R.M. 2007. Molecular phylogenetic analysis in Hammondia-like organisms based on partial Hsp70 coding sequences. Parasitology. 134:1195-1203.

Interpretive Summary: The 70-kDa heat shock protein (Hsp70) sequences are considered one of the most conserved proteins in all domain of life from Archaea to eukaryotes. Hammondia heydorni, H. hammondi, Toxoplasma gondii, Neospora hughesi and N. caninum (Hammondia-like organisms) are closely related tissue cyst-forming coccidians that belong to the sub-family Toxoplasmatinae. The phylogenetic reconstruction using cytoplasmic Hsp70 coding genes of Hammondia-like organisms revealed the genetic sequences of T. gondii, Neospora spp. and H. heydorni to possess similar level of evolutionary distance. In addition, at least two distinct genetic groups could be recognized among the H. heydorni isolates. Such results are in agreement with those obtained with internal transcribed spacer-1 rDNA (ITS-1) sequences. In order to compare the nucleotide diversity among different taxonomic levels within Apicomplexa, Hsp70 coding sequences of the following apicomplexan organisms were included in this study: Cryptosporidium, Theileria, Babesia, Plasmodium and Cyclospora. Such analysis revealed the Hammondia-like organism as the lowest divergent group when compared to other groups within the phylum Apicomplexa. In conclusion, the Hsp70 coding sequences proved to be a valuable genetic marker for phylogenetic reconstruction and may constitute a good candidate to be used with other genes for species phylogeny within this group of organisms.

Technical Abstract: The 70-kDa heat shock protein (Hsp70) sequences are considered one of the most conserved proteins in all domain of life from Archaea to eukaryotes. Hammondia heydorni, H. hammondi, Toxoplasma gondii, Neospora hughesi and N. caninum (Hammondia-like organisms) are closely related tissue cyst-forming coccidians that belong to the sub-family Toxoplasmatinae. The phylogenetic reconstruction using cytoplasmic Hsp70 coding genes of Hammondia-like organisms revealed the genetic sequences of T. gondii, Neospora spp. and H. heydorni to possess similar level of evolutionary distance. In addition, at least two distinct genetic groups could be recognized among the H. heydorni isolates. Such results are in agreement with those obtained with internal transcribed spacer-1 rDNA (ITS-1) sequences. In order to compare the nucleotide diversity among different taxonomic levels within Apicomplexa, Hsp70 coding sequences of the following apicomplexan organisms were included in this study: Cryptosporidium, Theileria, Babesia, Plasmodium and Cyclospora. Such analysis revealed the Hammondia-like organism as the lowest divergent group when compared to other groups within the phylum Apicomplexa. In conclusion, the Hsp70 coding sequences proved to be a valuable genetic marker for phylogenetic reconstruction and may constitute a good candidate to be used with other genes for species phylogeny within this group of organisms

Last Modified: 4/20/2014