Laboratorio di Biologia Cellulare, Istituto Superiore di Sanita', Rome, Italy.
By gel retardation assay and computational analysis we demonstrated a bent region in Trypanosoma lewisi, localized in two different classes of minicircles. We showed that in each minicircle this bent region is unique, adjacent to one of two highly conserved regions and characterized by adenine stretches. The same properties are conserved in the majority of minicircles from Trypanosomes tested so far. Therefore, we suggest that the genetic information could be located in a definite structure of minicircle DNA molecules rather than in the nucleotide sequence.