Overtwisted garden hoses, electrical wires, and ropes form plectonemes, supercoiling to lower their twist energy. In Michelle Wang's lab they overtwist DNA, to form the same plectonemes on a single-molecule basis.
Bryan Daniels aided in the interpretation of the experiment (PRL), generated a theory for the resulting jumps (PRE), and worked out the theory for the thermal nucleation of plectonemes under torque, (PRE). Last Modified: February 15, 2013.
This work supported by the Division of Materials Research of the U.S. National Science Foundation, through grant DMR-070167 and DMR-1005479.