Experimental ion permeability coefficients in different bilayers

Range Table - link
Organism Various
Reference Vorobyov I. et al., Ion-induced defect permeation of lipid membranes. Biophys J. 2014 Feb 4 106(3):586-97. doi: 10.1016/j.bpj.2013.12.027. p.592 table 3PubMed ID24507599
Primary Source See refs beneath table
Method Abstract: "[Investigators] have explored the mechanisms of uncatalyzed membrane ion permeation using atomistic simulations and electrophysiological recordings." P.586 left column top paragraph: "Here [investigators] have used molecular dynamics (MD) simulations and electrophysiological measurements to better understand and quantify charge-membrane transport processes."
Comments P.592 left column bottom paragraph to right column bottom paragraph: "Individual ion permeability coefficients are summarized in Table 3, along with apparent free energies of transfer and approximate peak free energies (using Eqs. 7, 8, and S6). Within each bilayer, the permeabilities to K+, GuanH+, and Cl− are similar. As expected from the concentration-independent conductance, the ion permeabilities are ∼10-fold less in 1.0 M than in 0.1 M salt. This corresponds to ∼1 kcal/mol increase in the estimated energy barriers for ion movement, or a similar reduction in interfacial binding, as suggested by [investigators'] simulations (Figs. 4 and S14, dashed and dotted pink lines). [Investigators'] results are consistent with those of previous studies in phospholipid vesicles. In Table 3, [they] list permeability coefficients for Na+, K+, and Cl− across bovine phosphatidylserine (PS) membrane (predominantly sn1 -18:0 and sn2 -18: 1-PS, SOPS) (ref 13)." See notes beneath table DPhPC=[1,2-diphytanoyl-sn-glycero-3-phosphocholine], PS= [phosphatidylserine], DOPC=[1,2-Dioleoyl-sn-glycero-3-phosphocholine], GuanH+=[arginine side chain analog guanidinium]
Entered by Uri M
ID 112546