The mechanism of channel formation by alamethicin as viewed by molecular dynamics simulations.

摘要: Alamethicin is a 20-residue channel-forming peptide that forms stable amphipathic alpha-helix in membrane and membrane-mimetic environments. This helix contains kink induced by central Gly-X-X-Pro sequence motif. channels are activated cis positive transbilayer voltage. Channel activation suggested to correspond voltage-induced insertion of alamethicin helices the bilayer. multi-conductance lipid bilayers. These formed parallel bundles transmembrane surrounding pore. A change number per bundle switches single channel conductance level. Molecular dynamics simulations different environments have been used explore its properties. include: (i) solution water methanol; (ii) at surface phosphatidylcholine bilayer; (iii) spanning (iv) 5, 6, 7 or 8 The total simulation time c. 30 ns. Thus, these provide set dynamic snapshots possible mechanism formation this peptide.