Monomorphic and Pleomorphic Trypanosoma Brucei Rhodesiense: Biochemical, Morphological and Ultrastructural Comparisons

Abstract

Monomorphic and Pleomorphic Trypanosoma Brucei Rhodesiense: Biochemical, Morphological and Ultrastructural Comparisons

The long slender and short stumpy forms of pleomorphic T . b. rhodesiense (LSHTM 180) have been compared to each other and to the monomorphic T. b. rhodesiense Liverpool Normal (Liv). 1. The agar film technique showed that morphologically the stumpy LSHTM 180 can be differentiated from the slender LSHTM 180 and the monomorphic T. b. rhodesiense (Liv) because it contains lipid granules. 2. Starch gel and cellulose acetate electrophoresis did not show any major differences in the isoenzyme profiles of 8 out of 9 enzymes studied. However, the presence of an aconitase band in the stumpy LSHTM 180 further differentiated it from the slender LSHTM 180 and the monomorphic T. b. rhodesiense (Liv). 3. Polypeptide profiles showed the presence of a 58,000 dalton polypeptide in extracts of both the slender and monomorphic trypomastigotes which was absent in the stumpy form. 4. Like starch gel and cellulose acetate electrophoresis, enzyme assays gave little information as to differences between the 3 trypomastigotes . There was, however, a higher NADP-isocitrate dehydrogenase activity in the stumpy form than the other two. 5. Ultrastructural studies showed the stumpy form had more cristae in the mitochondrion than either the slender LSHTM 180 or the monomorphic T. b. rhodesiense (Liv). 6. Trypomastigotes of the pleomorphic strain LSHTM 180 infected the ependymal cells of the choroid plexus, but the monomorphic T. b. rhodesiense (Liv) was unable to do this.