COMPARATIVE CHROMATIN ANALYSIS OF TRYPANOSOMA-CONGOLENSE

The chromatin of Trypanosoma congolense was analyzed by electron micro scopy. The chromatin is organized as nucleosome filaments but does not form a 30 nm fiber. There are five groups of histones, including a hi stone H1-like protein, which has a molecular weight within the range o f the core histones, and is extremely hydrophilic. Weak histone-histon e interaction, a typical feature of trypanosome chromatin, was found T hese results are similar to those for T. cruzi and T. b. brucei, bur d iffer significantly from those for higher eukaryotes. The results conf irm the model of trypanosome chromatin, and support the theory of thei r early separation from the other eukaryotes during the evolution. T. congolensis is an excellent model for chromatin research on trypanosom es, because it is easy to cultivate and its chromatin has, a relativel y high stability, compared to that of other trypanosomes.