Biochemical characterization of some raptor trypanosomes. I. In vitro cultivation and lectin-binding studies

Abstract

Nine trypanosome strains from five species of raptors were cultivated in vitro in a monophasic medium. Two morphologically distinct trypanosomes were observed in culture: those from American kestrels (Falco sparverius) were smaller than the other strains. The two kestrel (KT) trypanosome strains showed in vitro growth kinetics that differed from the larger trypanosomes, and the KT strains, unlike the others, required hemin in the medium for growth. The effectiveness of eight plant lectins to induce the agglutination of cultured trypanosomes was studied as a means of differentiating the various strains. It was found that lectins from Lens culinaris and Ricinus communis (type I) were particularly effective in distinguishing the KT strains from the other raptor trypanosome strains. Based on the results of experiments in which lectin-mediated trypanosome agglutination was inhibited by the addition of various monosaccharides, it is concluded that all of the avian trypanosomes studied express surface methyl α-D-mannoside, D(+)-galactose, and (or) α-lactose. Only the relatively large raptor trypanosome isolates expressed N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, and α-L(−)-fucose on their surfaces. The differences in lectin-binding characteristics between the two morphologic types of raptor trypanosome were as great as those among each of the avian trypanosomes and the mammalian trypanosomatids Leishmania chagasi and Trypanosoma rhodesiense.

<p><strong><em>Trypanosoma</em> <em>naviformis</em> sp. nov. (Kinetoplastidae: Trypanosomatidae) from widespread African songbirds, the Olive sunbird (<em>Cyanomitra</em> <em>olivacea</em>) and Yellow-whiskered greenbul (<em>Andropadus</em> <em>latirostris</em>)</strong></p>

“…characterization, and sometimes appears to be more informative than what is found in blood smears from hosts (Zídková et al, 2012). It should be mentioned that in vitro cultivation methods may also be limited in their application to taxonomy due to marked sensitivity and variation of morphology of parasite strains during development at different temperatures and media (Kirkpatrick and Terway-Thompson, 1986;Kučera, 1986). However, with cultured trypanosomes, it would be much more straightforward to obtain pure DNA, and thus facilitate molecular and phylogenetic analyses.…”