Abstract:
:The interaction of α-helical peptides with lipid bilayers is central to our understanding of the physicochemical principles of biological membrane organization and stability. Mutations that alter the position or orientation of an α-helix within a membrane, or that change the probability that the α-helix will insert into the membrane, can alter a range of membrane protein functions. We describe a comparative coarse-grained molecular dynamics simulation methodology, based on self-assembly of a lipid bilayer in the presence of an α-helical peptide, which allows us to model membrane transmembrane helix insertion. We validate this methodology against available experimental data for synthetic model peptides (WALP23 and LS3). Simulation-based estimates of apparent free energies of insertion into a bilayer of cystic fibrosis transmembrane regulator-derived helices correlate well with published data for translocon-mediated insertion. Comparison of values of the apparent free energy of insertion from self-assembly simulations with those from coarse-grained molecular dynamics potentials of mean force for model peptides, and with translocon-mediated insertion of cystic fibrosis transmembrane regulator-derived peptides suggests a nonequilibrium model of helix insertion into bilayers.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Hall BA,Chetwynd AP,Sansom MSdoi
10.1016/j.bpj.2011.02.041subject
Has Abstractpub_date
2011-04-20 00:00:00pages
1940-8issue
8eissn
0006-3495issn
1542-0086pii
S0006-3495(11)00261-Xjournal_volume
100pub_type
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