A Metazoan/Plant-like Capping Enzyme and Cap Modified Nucleotides in the Unicellular Eukaryote Trichomonas vaginalis
Figure 1
Sequence alignments of capping enzymes guanylyltransferase and triphosphatase.
Homo sapiens (Hsa), Saccharomyces cerevisiae (Sce), Mus musculus (Mus), Drosophila melanogaster (Dme), Oryza sativa (Osa), Caenorhabditis elegans (Cel), Plasmodium falciparum (Pfa), Encephalitozoon cuniculi (Ecu), Crithidia fasciculata (Cfa), Trypanosoma brucei gambiense (Tbr), Giardia lamblia (Gla) and T. vaginalis (Tva) capping enzymes are shown. A. Sequence alignment of TvCE TPase reveals conservation with ‘metazoa/plant sequences and presence of the ‘P-loop’ active site. Identity and similarity are indicated in black and gray boxes, respectively. H125S and C126S substitutions in TvCE are indicated by arrowheads. B. GTase signature motifs conserved in all examined enzymes are indicated (I, III, IIIa, IV, V and VI). Numbers indicate the number of amino acid residues separating the motifs in different proteins. Essential amino acids for yeast (Sce) GTase are denoted by asterisks. The R526A substitution in TvCE is indicated by an arrowhead.