Spectral rate theory for two-state kinetics

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Jan-Hendrik Prinz, John D. Chodera, and Frank Noé.
Phys. Rev. X 4:011020, 2014. [DOI] [PDF]

We present a new mathematical framework for unifying various two-state rate theories presented in the physical chemistry literature over many decades, and provide a quantitative way to measure reaction coordinate quality.

The limitations of constant-force-feedback experiments

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Phillip J. Elms, John D. Chodera, Carlos J. Bustamante, and Susan Marqusee.
Biophys. J. 103:1490, 2012. [DOI] [PDF]

Popular constant-force-feedback single-molecule experiments can cause severe artifacts in single-molecule force spectroscopy data.  We demonstrate a simple alternative that eliminates these artifacts.

The molten globule state is unusually deformable under mechanical force

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Philip J. Elms, John D. Chodera, Carlos Bustamante, and Susan Marqusee.
Proc. Natl. Acad. Sci. USA 109:3796, 2012. [DOI] [PDF]

We measure the physical properties of the molten globule state of apo-myoglobin, and show that it is unusually deformable compared to typical protein native states.

The ribosome modulates nascent protein folding

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Christian M. Kaiser, Daniel H. Goldman, John D. Chodera, Ignacio Tinoco Jr., and Carlos Bustamante.
Science 334:1723, 2011. [DOI] [PDF]

Using single-molecule force spectroscopy, we show how the ribosome itself modulates the folding dynamics of nascent protein chains emerging from the exit tunnel.

Nonequilibrium candidate Monte Carlo is an efficient tool for equilibrium simulation

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Jerome P. Nilmeier, Gavin E. Crooks, David D. L. Minh, and John D. Chodera. 
Proc. Natl. Acad. Sci. USA 108:E1009, 2011. [DOI] [PDF]

We present a significant generalization of Monte Carlo methods that provide an enormously useful tool for enhancing the efficiency of molecular simulations and enabling molecular design.

Keywords: NCMC; Monte Carlo; Metropolis-Hastings; acceptance rates; molecular dynamics

Bayesian hidden Markov model analysis of single-molecule force spectroscopy: Characterizing kinetics under measurement uncertainty

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John D. Chodera, Phillip Elms, Frank Noé, Bettina Keller, Christian M. Kaiser, Aaron Ewall-Wice, Susan Marqusee, Carlos Bustamante, and Nina Singhal Hinrichs.
preprint: [arXiv]

We describe the general theory and implementation for a Bayesian extension of hidden Markov models applicable to the characterization of how measurement uncertainty and finite statistics can impact the confidence in rate constants and conformational state properties.

Estimating equilibrium ensemble averages using multiple time slices from driven nonequilibrium processes

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Estimating equilibrium ensemble averages using multiple time slices from driven nonequilibrium processes: Theory and application to free energies, moments, and thermodynamic length in single-molecule pulling experiments
David D. L. Minh and John D. Chodera
J. Chem. Phys. 134:024111, 2011. [DOI] [PDF]

We derive a new estimator for estimating equilibrium expectations from nonequilibrium experiments, and show how it can be used to estimate a variety of useful quantities in simulated single-molecule force spectroscopy experiments.

Optimal estimators and asymptotic variances for nonequilibrium path-ensemble averages

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David D. D. L. Minh and John D. Chodera.
J. Chem. Phys. 131:134110, 2009. [DOI] [PDF]

We derive an optimal estimator and corresponding statistical uncertainties for inferring expectations of bidirectional nonequilibrium processes.  These estimators have widespread applicability in single-molecule biophysical force-spectroscopy experiments and nonequilibrium molecular simulations.

Statistically optimal analysis of samples from multiple equilibrium states

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Michael R. Shirts and John D. Chodera.  
J. Chem. Phys. 129:124105, 2008. [DOI] [PDF]

We present a highly general, statistically optimal approach for producing estimates of free energies and equilibrium expectations from multiple simulations that provably extracts all useful information from the data.

Keywords: Multistate Bennett acceptance ratio; MBAR; Bennett acceptance ratio; BAR; molecular dynamics; Monte Carlo; replica exchange