Isolation of the flagellum and characterization of the paraxial structure of Herpetomonas megaseliae.

It was observed in thin sections that the flagellum from Herpetomonas megaseliae, a protozoan of the Trypanosomatidae family, has, besides the axoneme, a filamentous lattice-like structure, the paraxial rod. Crithidia deanei, a protozoan of the same family, does not possess a paraxial rod in its flagellum. The flagella of these two trypanosomatids were isolated. Cultures were sonified and fractionated thus resulting the following fractions: total homogenates, deflagellated cell bodies, crude flagellar fraction and purified flagellar fraction from both H. megaseliae and C. deanei. The flagellar fractions are very pure and the flagella have their structures well preserved: axonemes and paraxial structures, where they exist, are intact, associated with one another and surrounded by the flagellar membrane. A comparative analysis of the purified flagellar fractions from both trypanosomatids was made using polyacrylamide gel electrophoresis. Two protein bands, with molecular weights of 78,000 and 73,000 daltons, which were enriched along the process of purification of the flagella from H. megaseliae, were found to correspond to the main components of the paraxial structure. These two bands were not observed in the purified flagellar fraction from C. deanei.