ISSN:
1432-1432
Keywords:
Key words:Trichomonas tenax— Elongation factor 1α— Elongation factor 2 — Mitochondrion-lacking protozoa — Protein evolution — Phylogenetic tree
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract. Major parts of amino-acid-coding regions of elongation factor (EF)-1α and EF-2 in Trichomonas tenax were amplified by PCR from total genomic DNA and the products were cloned into a plasmid vector, pGEM-T. The three clones from each of the products of the EF-1α and EF-2 were isolated and sequenced. The insert DNAs of the clones containing EF-1α coding regions were each 1,185 bp long with the same nucleotide sequence and contained 53.1% of G + C nucleotides. Those of the clones containing EF-2 coding regions had two different sequences; one was 2,283 bp long and the other was 2,286 bp long, and their G + C contents were 52.5 and 52.9%, respectively. The copy numbers of the EF-1α and EF-2 gene per chromosome were estimated as four and two, respectively. The deduced amino acid sequences obtained by the conceptual translation were 395 residues from EF-1α and 761 and 762 residues from the EF-2s. The sequences were aligned with the other eukaryotic and archaebacterial EF-1αs and EF-2s, respectively. The phylogenetic position of T. tenax was inferred by the maximum likelihood (ML) method using the EF-1α and EF-2 data sets. The EF-1α analysis suggested that three mitochondrion-lacking protozoa, Glugea plecoglossi, Giardia lamblia, and T. tenax, respectively, diverge in this order in the very early phase of eukaryotic evolution. The EF-2 analysis also supported the divergence of T. tenax to be immediately next to G. lamblia.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/PL00006127
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