Résumé
Trypanosome stocks isolated from bats (Chiroptera) and belonging to the subgenus
Schizotrypanum were analyzed by multilocus enzyme electrophoresis (MLEE) at 22 loci, random amplified polymorphic DNA (RAPD) with 14 primers and/or cytochrome
b nucleotide sequence. Bat trypanosomes belonged to the species
Trypanosoma cruzi marinkellei (10 stocks),
Trypanosoma dionisii (four stocks) and
Trypanosoma vespertilionis (three stocks). One
T. rangeli stock and seven stocks of
T. cruzi sensu stricto, the agent of Chagas disease, were included for comparison. The homology of several RAPD fragments shared by distinct species was verified by hybridization. The sequence of a 516-nucleotide portion of the maxicircle-encoded cytochrome
b (
CYb) coding region was determined in representative stocks of the species under study. Phylogenetic analysis of the data confirmed the previous taxonomic attribution of these bat trypanosomes based on biological, epidemiological and ecological features. However, a new finding was that within
T. cruzi marinkellei two major subdivisions could be distinguished, T.c.m. I, found in the spear-nose bats
Phyllostomus discolor and
Phyllostomus hastatus, and T.c.m. II, from
P. discolor. In addition, the
T. c. marinkellei ‘Z’ stock from a short-tailed bat (
Carollia perspicillata) was distantly related to these two subdivisions, and the monophyly of
T. c. marinkellei is unclear based on the present data. Based on the present sample, the European species
T. dionisii and
T. vespertilionis appeared to be more homogeneous. RAPD and
CYb data both suggested the monophyly of a group composed of
T. cruzi and the two major subdivisions of
T. cruzi marinkellei. This study shows that MLEE, RAPD and
CYb can be used for taxonomic assignment and provide valuable phylogenetic information for strains and taxa within the subgenus
Schizotrypanum. An evolutionary scenario in which the broad host-range parasite
T. cruzi would be derived from a bat-restricted trypanosome ancestor is discussed.