| Comments |
P.591 right column 2nd paragraph: "Table 2 summarizes [investigators'] experimental results for membrane conductances in different bilayers. For the KCl, NaCl, and GuanHCl salts tested, the conductances vary only within an order of magnitude, suggesting that the permeation process is nonselective. The conductances are similar in bilayers formed by ether or ester phospholipids, which have dipole potentials differing by 100–250 mV (ref 28), corresponding to an energy difference of 2.4–6.0 kcal/mol. This suggests that the permeating ions sense little of the membrane dipole potential, consistent with an ion-induced-defect permeation mechanism." See notes beneath table DPhPC=[1,2-diphytanoyl-sn-glycero-3-phosphocholine], GuanH+=[arginine side chain analog guanidinium] |