title: Convergence of molecular dynamics simulations of membrane proteins.
abstract: The central question in evaluating almost any result from a molecular dynamics simulation is whether the calculation has converged. Unfortunately, assessing the ergodicity of a single trajectory is very difficult to do. In this work, we assess the sampling of molecular dynamics simulations of the membrane protein rhodopsin by comparing the results from 26 independent trajectories, each run for 100 ns. By examining principal components and cluster populations, we show that rhodopsin's fluctuations are not well described by 100 ns of dynamics, and that the sampling is not fully converged even for individual loops. The results serve as a reminder of the caution required when interpreting molecular dynamics simulations of macromolecules.
authors.affiliation: IBM T. J. Watson Research Center, Yorktown Heights, New York 10598, USA. agrossf@us.ibm.com
authors.forename: Alan
authors.initials: A
authors.lastname: Grossfield
authors.forename: Scott E
authors.initials: SE
authors.lastname: Feller
authors.forename: Michael C
authors.initials: MC
authors.lastname: Pitman
mesh_terms: D019295:Computational Biology; D003198:Computer Simulation; D008563:Membrane Lipids / Q000737:chemistry; D008565:Membrane Proteins / Q000737:chemistry*; D008958:Models, Molecular; D010713:Phosphatidylcholines / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000737:chemistry; D025341:Principal Component Analysis; D012243:Rhodopsin / Q000737:chemistry*
chemical_list: D008563:Membrane Lipids; D008565:Membrane Proteins; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; C483858:phosphatidylethanolamine; D012243:Rhodopsin