American Chemical Society
bi901166n_si_001.pdf (1.84 MB)

Simulations of the BM2 Proton Channel Transmembrane Domain from Influenza Virus B

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journal contribution
posted on 2009-10-27, 00:00 authored by Sarah L. Rouse, Timothy Carpenter, Phillip J. Stansfeld, Mark S. P. Sansom
BM2 is a small integral membrane protein from influenza B virus which forms proton-permeable channels. Coarse-grained (CG) molecular dynamics simulations have been used to produce a model of the BM2 channel by self-assembly of a tetrameric bundle of BM2 transmembrane helices in a lipid bilayer. The BM2 channel model is conformationally stable on a 5 μs time scale. This CG model was converted to atomistic resolution to refine interhelix and channel−water interactions. Atomistic molecular dynamics simulations indicate that the BM2 channel is closed when no more than two of the four His19 residues are protonated. Protonating a third His19 side chain initiates a conformational change that opens the channel. In summary, our simulations suggest a common mechanism for BM2 and A/M2, whereby changes in helix packing play a functional role in channel gating.