Free energy reconstruction in bidirectional force spectroscopy experiments: the effect of the device stiffness.
J Phys Chem B
; 114(7): 2509-16, 2010 Feb 25.
Article
em En
| MEDLINE
| ID: mdl-20121079
ABSTRACT
In force spectroscopy single-molecule experiments, an individual molecule, usually a polymer, is mechanically stretched by means of an externally controlled driving potential. Typically, the stiffness of this potential is much smaller than the stiffness of the potential of mean force along the molecular extension coordinate. Here we discuss how such a disparity alters the free energy and the reversibility of the driven system, with respect to the pristine molecular system under examination. In particular, by simulating unfolding/refolding experiments of a small protein, we examine the traits of the potential of mean force that are responsible for the dramatic amount of work dissipated in experiments using a soft device. Finally, we show that in bidirectional experiments the free energy of the free molecular system can be easily recovered by appropriate reweighting methods.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas
Idioma:
En
Revista:
J Phys Chem B
Assunto da revista:
QUIMICA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Itália