TY  - JOUR
UR  - http://link.aps.org/doi/10.1103/PhysRevLett.106.138102
JF  - Physical Review Letters
AV  - public
TI  - Compaction and tensile forces determine the accuracy of folding landscape parameters from single molecule pulling experiments
KW  - PACS: 87.10.-e
KW  -  87.15.Cc
KW  -  87.64.Dz
KW  -  87.80.Nj

Y1  - 2011/03//
N2  - We establish a framework for assessing whether the transition state location of a biopolymer, which can be inferred from single molecule pulling experiments, corresponds to the ensemble of structures that have equal probability of reaching either the folded or unfolded states (Pfold=0.5). Using results for the forced unfolding of a RNA hairpin, an exactly soluble model, and an analytic theory, we show that Pfold is solely determined by s, an experimentally measurable molecular tensegrity parameter, which is a ratio of the tensile force and a compaction force that stabilizes the folded state. Applications to folding landscapes of DNA hairpins and a leucine zipper with two barriers provide a structural interpretation of single molecule experimental data. Our theory can be used to assess whether molecular extension is a good reaction coordinate using measured free energy profiles.
A1  - Morrison, Greg
A1  - Hyeon, Changbong
A1  - Hinczewski, Michael
A1  - Thirumalai, D.
SN  - 0031-9007
PB  - American Physical Society
N1  - © 2011 American Physical Society
ID  - eprints1825
VL  - 106
ER  -