Invariance of single-file water mobility in gramicidin-like peptidic pores as function of pore length.

ABSTRACT: We investigated the structural and energetic determinants underlying water permeation through peptidic nanopores, motivated by recent experimental findings that indicate that water mobility in single-file water channels displays nonlinear length dependence. To address the molecular mechanism determining the observed length dependence, we studied water permeability in a series of designed gramicidin-like channels of different length using atomistic molecular dynamics simulations. We found that within the studied range of length the osmotic water permeability is independent of pore length. This result is at variance with textbook models, where the relationship is assumed to be linear. Energetic analysis shows that loss of solvation rather than specific water binding sites in the pore form th

SUBMITTER: Portella G 

PROVIDER: S-EPMC1868973 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature