Principal component analysis of molecular dynamics simulations is a popular method to account for the essential dynamics of the system on a low-dimensional free energy landscape. Using Cartesian coordinates, first the translation and overall rotation need to be removed from the trajectory. Since the rotation depends via the moment of inertia on the molecule's structure, this separation is only straightforward for relatively rigid systems. Adopting millisecond molecular dynamics simulations of the folding of villin headpiece and the functional dynamics of BPTI provided by D. E. Shaw Research, it is demonstrated via a comparison of local and global rotational fitting that the structural dynamics of flexible molecules necessarily results in a mixing of overall and internal motion. Even for the small-amplitude functional motion of BPTI, the conformational distribution obtained from a Cartesian principal component analysis therefore reflects to some extend the dominant overall motion rather than the much smaller internal motion of the protein. Internal coordinates such as backbone dihedral angles, on the other hand, are found to yield correct and well-resolved energy landscapes for both examples. The virtues and shortcomings of the choice of various fitting schemes and coordinate sets as well as the generality of these results are discussed in some detail.
Skip Nav Destination
Article navigation
7 July 2014
Research Article|
July 07 2014
Principal component analysis of molecular dynamics: On the use of Cartesian vs. internal coordinates
Florian Sittel;
Florian Sittel
Biomolecular Dynamics, Institute of Physics and Freiburg Institute for Advanced Studies (FRIAS),
Albert Ludwigs University
, 79104 Freiburg, Germany
Search for other works by this author on:
Abhinav Jain;
Abhinav Jain
Biomolecular Dynamics, Institute of Physics and Freiburg Institute for Advanced Studies (FRIAS),
Albert Ludwigs University
, 79104 Freiburg, Germany
Search for other works by this author on:
Gerhard Stock
Gerhard Stock
a)
Biomolecular Dynamics, Institute of Physics and Freiburg Institute for Advanced Studies (FRIAS),
Albert Ludwigs University
, 79104 Freiburg, Germany
Search for other works by this author on:
a)
E-mail: stock@physik.uni-freiburg.de
J. Chem. Phys. 141, 014111 (2014)
Article history
Received:
April 11 2014
Accepted:
June 09 2014
Citation
Florian Sittel, Abhinav Jain, Gerhard Stock; Principal component analysis of molecular dynamics: On the use of Cartesian vs. internal coordinates. J. Chem. Phys. 7 July 2014; 141 (1): 014111. https://doi.org/10.1063/1.4885338
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Pay-Per-View Access
$40.00
Citing articles via
DeePMD-kit v2: A software package for deep potential models
Jinzhe Zeng, Duo Zhang, et al.