Toroidal DNA: Topology, geometry and electrostatics

Toroidal DNA condensates have received considerable attention as a model of ordered DNA condensation. Geometry and topology of fibre bundles can be ef ficient tools in order to study these structures, Such methods have given f ruitful results when considering toroidal vesicles made of amphiphile films and blue phases structures observed in liquid crystals made of long chiral molecules, We give, in this paper, the geometrical arguments supporting th is description. Then, we show how electrostatic interactions could be studi ed using curved spaces. We show that it is possible to have conditions resu lting in attractive interaction between DNA molecules in the presence of po sitive charges.