Fig. 6. Trypanosoma brucei minichromosomes with single-strand overhangs stained with SSB. Non-cross-linked minichromosomes enriched by sucrose gradient sedimentation were incubated with E.coli SSB and prepared for EM as described in Materials and methods, including adsorption to thin carbon foils, dehydration and rotary shadowcasting with tungsten. (A) A 31 kb minichromosome with single-stranded overhangs at both ends. The overhangs on this molecule are longer than most and were selected for greater visibility at low magnification. (B–E) Individual minichromosome ends with SSB bound. The size of the particle in (E) corresponds to a single SSB tetramer. Shown in reverse contrast. Bar equals 0.5 µm (A) and 0.27 µm (B–E).