Critical Torque for Kink Formation in Double-Stranded DNA

We measure the bending energy of double-stranded DNA in the nonlinear (sharply bent) regime. The measurements are obtained from the melting curves of stressed DNA ring molecules. The nonlinear elastic behavior is captured by a single parameter: the critical torque τ_{c} at which the molecule develops a kink. In this regime, the elastic energy is linear in the kink angle. This phenomenology is the same as for the previously reported case of nicked DNA. For the sequences examined, we find τ_{c}=31 pN×nm. This critical torque corresponds to a characteristic energy scale (π/2)τ_{c}=12 kT_{room} relevant for molecular biology processes associated with DNA bending.

Abstract licence: CC BY

33 more references, whose wording the paper’s licence keeps private.

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.