Implicit membrane treatment of buried charged groups: application to peptide translocation across lipid bilayers.

ABSTRACT: The energetic cost of burying charged groups in the hydrophobic core of lipid bilayers has been controversial, with simulations giving higher estimates than certain experiments. Implicit membrane approaches are usually deemed too simplistic for this problem. Here we challenge this view. The free energy of transfer of amino acid side chains from water to the membrane center predicted by IMM1 is reasonably close to all-atom free energy calculations. The shape of the free energy profile, however, for the charged side chains needs to be modified to reflect the all-atom simulation findings (IMM1-LF). Membrane thinning is treated by combining simulations at different membrane widths with an estimate of membrane deformation free energy from elasticity theory. This approach is first tested on the

SUBMITTER: Lazaridis T 

PROVIDER: S-EPMC4082734 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature