user-friendly commercial instruments. AFM has been employed on
several types of biological macromolecules, mechanically unfolding
proteins\citep{carrion-vazquez99a} and forcing structural transitions
-in DNA\citep{rief99} and polysaccharides\citep{rief97b}. An
+in DNA\citep{rief99} and polysaccharides\citep{rief97a}. An
AFM\index{AFM} uses a sharp tip integrated at the end of a cantilever
to interact with the sample. Cantilever bending is measured by a
laser reflected off the cantilever and incident on a position
title = "A simple method for probing the mechanical unfolding pathway of
proteins in detail",
year = 2002,
+ month = sep,
+ day = 17,
journal = PNAS,
volume = 99,
number = 19,
}
@article { rief97a,
- author = MRief #" and "# MGautel #" and "# FOesterhelt #" and "# JFernandez
- #" and "# HEGaub,
- title = "Reversible Unfolding of Individual Titin Immunoglobulin Domains by
- {AFM}",
- year = 1997,
- journal = SCI,
- volume = 276,
- number = 5315,
- pages = "1109--1112",
- doi = "10.1126/science.276.5315.1109",
- eprint = "http://www.sciencemag.org/cgi/reprint/276/5315/1109.pdf",
- url = "http://www.sciencemag.org/cgi/content/abstract/276/5315/1109",
- note = "Seminal paper for force spectroscopy on Titin. Cited by
- \citet{dietz04} (ref 9) as an example of how unfolding large proteins
- is easily interpreted (vs.\ confusing unfolding in bulk), but Titin is
- a rather simple example of that, because of its globular-chain
- structure.",
- project = "Energy Landscape Roughness"
-}
-
-@article { rief97b,
author = MRief #" and "# FOesterhelt #" and "# BHeymann #" and "# HEGaub,
title = "Single Molecule Force Spectroscopy on Polysaccharides by Atomic
Force Microscopy",
reversible and was corroborated by molecular dynamics calculations."
}
+@article { rief97b,
+ author = MRief #" and "# MGautel #" and "# FOesterhelt #" and "# JFernandez
+ #" and "# HEGaub,
+ title = "Reversible Unfolding of Individual Titin Immunoglobulin Domains by
+ {AFM}",
+ year = 1997,
+ month = may,
+ day = 16,
+ journal = SCI,
+ volume = 276,
+ number = 5315,
+ pages = "1109--1112",
+ doi = "10.1126/science.276.5315.1109",
+ eprint = "http://www.sciencemag.org/cgi/reprint/276/5315/1109.pdf",
+ url = "http://www.sciencemag.org/cgi/content/abstract/276/5315/1109",
+ note = "Seminal paper for force spectroscopy on Titin. Cited by
+ \citet{dietz04} (ref 9) as an example of how unfolding large proteins
+ is easily interpreted (vs.\ confusing unfolding in bulk), but Titin is
+ a rather simple example of that, because of its globular-chain
+ structure.",
+ project = "Energy Landscape Roughness"
+}
+
@article { rief98,
author = MRief #" and "# JFernandez #" and "# HEGaub,
title = "Elastically Coupled Two-Level Systems as a Model for Biopolymer
the pulling direction. The Monte Carlo simulation method has been
used since the first report of mechanical unfolding experiments using
the AFM%
-\citep{rief97b,rief97a,rief98,carrion-vazquez99a,best02,zinober02,jollymore09},
+\citep{rief97a,rief97b,rief98,carrion-vazquez99a,best02,zinober02,jollymore09},
but these previous implementations are neither fully described nor
publicly available.
a big-picture overview before diving into the more technical papers.
There are two main approaches to modeling protein domain unfolding under tension: Bell's and Kramers'\citep{schlierf06,dudko06,hummer03}.
-Bell introduced his model in the context of cell adhesion\citep{bell78}, but it has been widely used to model mechanical unfolding in proteins\citep{rief97a,carrion-vazquez99a,schlierf06} due to it's simplicity and ease of use\citep{hummer03}.
+Bell introduced his model in the context of cell adhesion\citep{bell78}, but it has been widely used to model mechanical unfolding in proteins\citep{rief97b,carrion-vazquez99a,schlierf06} due to it's simplicity and ease of use\citep{hummer03}.
Kramers introduced his theory in the context of thermally activated barrier crossings, which is how we use it here.
There is an excellent review of Kramers' theory in \citet{hanggi90}.
\subsection{Evolution of unfolding modeling}
Evans introduced the saddle-point Kramers' approximation in a protein unfolding context 1997 (\citet{evans97} Eqn.~3).
-However, early work on mechanical unfolding focused on the simper Bell model\citep{rief97a}.%TODO
+However, early work on mechanical unfolding focused on the simper Bell model\citep{rief97b}.%TODO
In the early `00's, the saddle-point/steepest-descent approximation to Kramer's model (\citet{hanggi90} Eqn.~4.56c) was introduced into our field\citep{dudko03,hyeon03}.%TODO
By the mid `00's, the full-blown double-integral form of Kramer's model (\citet{hanggi90} Eqn.~4.56b) was in use\citep{schlierf06}.%TODO
\subsection{History of experimental AFM unfolding experiments}
\begin{itemize}
- \item \citet{rief97a}:
+ \item \citet{rief97b}:
\end{itemize}
\subsection{History of experimental laser tweezer unfolding experiments}