Supercoiled DNA; plectonemic structure and liquid crystal formation
van der Maarel, J R C
Zakharova, S S
Egelhaaf, Stefan U
We have investigated the phase behaviour of pUC18 plasmid solutions with phase separation experiments and polarized light microscopy. Furthermore, the configuration of the superhelix is monitored with small-angle neutron scattering. The phase diagram is interpreted with liquid crystal theory including the effects of charge, orientation entropy, excluded volume, as well as the elastic, entropic and electrostatic contributions to the molecular free energy.