Torque spectroscopy of DNA: base-pair stability, boundary effects, backbending, and breathing dynamics.

ABSTRACT: Changes in global DNA linking number can be accommodated by localized changes in helical structure. We have used single-molecule torque measurements to investigate sequence-specific strand separation and Z-DNA formation. By controlling the boundary conditions at the edges of sequences of interest, we have confirmed theoretical predictions of distinctive boundary-dependent backbending patterns in torque-twist relationships. Abrupt torque jumps are associated with the formation and collapse of DNA bubbles, permitting direct observations of DNA breathing dynamics.

SUBMITTER: Oberstrass FC 

PROVIDER: S-EPMC3696636 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature