The chromatin of Trypanosoma congolense
was analyzed by
electron microscopy. The chromatin is organized as nucleosome
filaments but does not form a 30 nm fiber. There are five groups of
histones, including a histone H1-like protein, which has a molecular
weight within the range of the core histones, and is extremely
hydrophilic. Weak histone-histone interaction, a typical feature of
trypanosome chromatin, was found. These results are similar to those
for T. cruzi and T. b. brucei, but differ
significantly from those for higher eukaryotes. The results confirm
the model of trypanosome chromatin, and support the theory of their
early separation from the other eukaryotes during the evolution.
T. congolensis is an excellent model for chromatin research
on trypanosomes, because it is easy to cultivate and its chromatin
has, a relatively high stability, compared to that of other
trypanosomes.