These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Two-dimensional replica exchange approach for peptide-peptide interactions.
    Author: Gee J, Shell MS.
    Journal: J Chem Phys; 2011 Feb 14; 134(6):064112. PubMed ID: 21322666.
    Abstract:
    The replica exchange molecular dynamics (REMD) method has emerged as a standard approach for simulating proteins and peptides with rugged underlying free energy landscapes. We describe an extension to the original methodology--here termed umbrella-sampling REMD (UREMD)--that offers specific advantages in simulating peptide-peptide interactions. This method is based on the use of two dimensions in the replica cascade, one in temperature as in conventional REMD, and one in an umbrella sampling coordinate between the center of mass of the two peptides that aids explicit exploration of the complete association-dissociation reaction coordinate. To mitigate the increased number of replicas required, we pursue an approach in which the temperature and umbrella dimensions are linked at only fully associated and dissociated states. Coupled with the reweighting equations, the UREMD method aids accurate calculations of normalized free energy profiles and structural or energetic measures as a function of interpeptide separation distance. We test the approach on two families of peptides: a series of designed tetrapeptides that serve as minimal models for amyloid fibril formation, and a fragment of a classic leucine zipper peptide and its mutant. The results for these systems are compared to those from conventional REMD simulations, and demonstrate good convergence properties, low statistical errors, and, for the leucine zippers, an ability to sample near-native structures.
    [Abstract] [Full Text] [Related] [New Search]