Supplementary Figure 2: ATP fails to permeate mVDAC1 on the microsecond timescale.

(a,c) The z-position of the COM of the triphosphate tail and adenine ring are plotted versus time for two simulations run with either a 0 or 50 mV electric field. The channel was centered at z = 0 and aligned along the z-axis. (b,d) The same trajectories, projected onto the x-y plane. For the simulation performed with a 50 mV field, the ATP was initiated in the upper bath; the simulation at 0 mV was initiated in the pore. Despite their different initial positions within the simulation box and applied voltage, the ATP in both simulations bind to the N-terminal helix and sample a similar set of conformations. The phosphate tail remains largely immobile over the full length of the simulation, whereas the adenine ring interacts with a number of moieties within the channel.