PHYLOGENETIC POSITION OF THE GIANT ANURAN TRYPANOSOMES TRYPANOSOMA CHATTONI, TRYPANOSOMA FALLISI, TRYPANOSOMA MEGA, TRYPANOSOMA NEVEULEMAIREI, AND TRYPANOSOMA RANARUM INFERREDFROM 18S rRNA GENE SEQUENCES

Abstract

Phylogenetic relationships within the kinetoplastid flagellates were inferred from comparisons of small-subunit ribosomal RNA gene sequences. These included 5 new gene sequences, Trypanosoma fallisi (2,239 bp), Trypanosoma chattoni (2,180 bp), Trypanosoma mega (2,211 bp), Trypanosoma neveulemairei (2,197 bp), and Trypanosoma ranarum (2,203 bp). Trees produced using maximum-parsimony and distance-matrix methods (least-squares, neighbor-joining, and maximum-likelihood), supported by strong bootstrap and quartet-puzzle analyses, indicated that the trypanosomes are a monophyletic group that divides into 2 major lineages, the salivarian trypanosomes and the nonsalivarian trypanosomes. The nonsalivarian trypanosomes further divide into 2 lineages, 1 containing trypanosomes of birds, mammals, and reptiles and the other containing trypanosomes of fish, reptiles, and anurans. Among the giant trypanosomes, T. chattoni is clearly shown to be distantly related to all the other anuran trypanosome species. Trypanosoma mega is closely associated with T. fallisi and T. ranarum, whereas T. neveulemairei and Trypanosoma rotatorium are sister taxa. The branching order of the anuran trypanosomes suggests that some toad trypanosomes may have evolved by host switching from frogs to toads.

Sexual differences in prevalence of a new species of trypanosome infecting túngara frogs

“…We extracted DNA directly from blood samples using DNeasy kits (Qiagen, Valencia, CA, USA) following the manufacturer's recommendations. Following Martin et al. (2002) , we examined 18S ribosomal RNA gene (18S rRNA).…”

“…As predicted, we found trypanosome infected male túngara frogs and thus implemented morphological and molecular methods to characterize and infer the phylogenetic relationship of this Trypanosoma species to other trypanosomes that parasitize other vertebrates that inhabit aquatic and marine environments. The characterization and phylogenetic relationships of this new Trypanosoma species provide new information on anuran trypanosomes, a group with poorly known taxonomic relationships ( Martin et al., 2002 ). In addition, we provide insights about the prevalence of this trypanosome species on its type host.…”

Phylogenetic position of the freshwater fish trypanosome, Trypanosoma ophiocephali (Kinetoplastida) inferred from the complete small subunit ribosomal RNA gene sequence

“…Molecular methods, in particular, the determination of small subunit rRNA (SSrRNA) sequences, have been commonly used to re-evaluate the phylogenetic relationships of trypanosomes in recent years (Jakes et al 2001; Sehgal et al 2001; Martin et al 2002; Votypka et al 2002, 2004; Gibson et al 2005; Davies et al 2005; Karlsbakk and Nylund 2006; Gu et al 2007b). These studies provided many results inconsistent with those from traditional morphological and ontogenetic characters (Sehgal et al 2001; Davies et al 2005; Karlsbakk and Nylund 2006; Gu et al 2007b).…”

Pathological Study of Blood Parasites in Rice Field Frogs,Hoplobatrachus rugulosus(Wiegmann, 1834)

“…The classification of anuran trypanosomes is still in confusion because some species may be polymorphic [7–9]. Trypanosoma rotatorium is a polymorphic species with a wide geographical distribution, while Trypanosoma chattoni is a monomorphic species that is found in Asia, Europe, and America [7, 10]. Hepatozoon spp.…”

“…In Thailand, a survey of mainly blood parasites and helminthes of amphibians has been undertaken [10–12]. There are few published data on the pathogenicity of blood parasites infections in amphibian hosts.…”