The position dependent diffusion coefficient, D(z), of <i>tyr</i> (NH₂/OH) and <i>tyr</i>⁺ (NH3+/OH) across a POPC bilayer with the bilayer center at z = 0.

<p>The diffusion for <i>tyr</i>⁺ remains relatively constant once inside the bilayer. This is likely due to a water channel being created in the POPC through a strong interaction of water with the </p><p></p><p></p><p></p><p></p><p>NH<mn>3</mn></p><mo>+</mo><p></p><p></p><p></p><p></p> group. The water follows <i>tyr</i>⁺ through and reduces its mobility while keeping it in a consistent environment. The <i>tyr</i> permeates without water and has mobility characteristics that correlate strongly with the bilayer density, including a densely packed region near the head groups and an area of high free volume at the center of the bilayer where the hydrocarbon tails meet.<p></p

The average change in the mean, ⟨Δ<i>μ</i>_bin⟩, as samples are added to the Bayesian hypothesis about the mean.

<p>For example, at <i>N</i> = 2, ⟨Δ<i>μ</i>_<i>bin</i>⟩ = ⟨<i>μ</i>_<i>bin</i>(2) − <i>μ</i>_<i>bin</i>(1)⟩, and the most probable value from each Bayesian distribution was used for <i>μ</i>_<i>bin</i>. The set averaged over was comprised of one bin every 1 Å (i.e. only every fifth bin was used). The fitted curve for <i>tyr</i>⁺ was calculated without the outlier at Sample 4, while the curve for <i>tyr</i> was fitted without Sample 7.</p

The permeability of tyramine calculated over the reported range of pK_<i>a</i> values for the amine group.

<p>The single standard error uncertainty for the simulated values (Slow conversion, Fast conversion, Mixed PMF) are plotted as black dotted lines, while the uncertainty for the experimental result is shown as black dashed lines. The inset is an expansion of the region where the plots converge.</p