Electrophoretic Mobility of Tubulin Subunits as a Criterion for Testing Relationships between Trichormonad Taxa

Abstract

Summary Electrophoretic mobility of tubulin subunits has been used to test relationships among six trichomonad species belonging to two major families of the Trichomonadida: the Monocercomonadidae (represented by Monocercomonassp. and Hypotrichomonas acosta) and the Trichomonadidae (represented by Trichomonas vaginalis, Tetra trichomonas gallinarum, Tritrichomonas foetus and Trichomitus batrachorum). SDS-PAGE performed under different conditions revealed differences in the electrophoretic behavior of tubulins from species belonging to different taxonomic groups. An important influence of urea and pH of the separating gel during migration of the tubulins has been detected. Moreover, in contrast to other protist groups, trichomonad tubulins did not exhibit any α/β inversion. Differential SDS binding to the tubulin due to sequence differences could be an explanation for the electrophoretic diversity observed. Comparison of electrophoretic mobility of tubulins allowed us to group the trichomonads analyzed in clusters which were in agreement with the molecular phylogeny based on large subunit rRNA sequences. Therefore the electrophoretic mobility of tubulins can be used to complement molecular phylogenetic approaches.