Table 2.
Oxygen permeability (mean ± SD), partitioning, and related values.
| System | PM (cm/s) a | aLb | PL (cm/s)c | h | l (nm)d | 〈S〉e- | KPf | DM(×10−6 cm2/s)g |
|---|---|---|---|---|---|---|---|
| POPC | 53 ± 2 | 1 | 53 ± 2 | 5.6 | 7.1 | 0.19 | 7.8 | 3.8 |
| POPC/Chol | 42 ± 2 | 1 | 42 ± 2 | 6.2 | 9.4 | 0.38 | 5.6 | 4.7 |
| K+chan/POPC | 24 ± 1 | 0.77 | 31 ± 1 | 6.2 | 8.4 | 0.23 | 6.6 | 2.3 |
| K+chan/POPC/Chol | 23 ± 1 | 0.73 | 32 ± 2 | 5.8 | 9.0 | 0.34 | 5.5 | 2.4 |
| K+chan/KCl/POPC | 29 ± 2 | 0.77 | 37 ± 2 | 6.2 | 8.4 | 0.22 | 7.7 | 2.3 |
Fractional area occupied by lipid.
Actual or apparent permeability of the lipid bilayer region, estimated from Eq. 3.
Membrane thickness, h, based on O2 free energy profiles, determined as in [11] (data not shown). Average total box length, l, normal to the bilayer (standard deviation = 0.1 nm).
Average lipid order parameter for carbons 4-8 of all POPC palmitoyl tails, as described in [17].
Membrane/water O2 partition coefficient, from depth-dependent O2 distribution profiles, averaged over the whole membrane.
Apparent whole-membrane diffusion coefficient, estimated from the relation in Eq. 1.