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Theoretical perspectives on ion-channel electrostatics: continuum and microscopic approaches

Published online by Cambridge University Press:  17 March 2009

Michael B. Partenskii  and
Peter C. Jordan
Peter C. Jordan
Affiliation:
Department of Chemistry, Brandeis University, Waltham, MA 02254–9110
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Extract

Peter Läuger introduced me (P.C.J.) to the field of ion-channel electrostatics while I was a sabbatical visitor at Konstanz in 1978–79. Läuger pointed out that the relative conductance of hydrophobic ions through phosphatidyl choline (PC) and glyceryl monooleate (GMO) membranes differed by a factor of about 100 (Hladky & Haydon, 1973), quite consistent with the difference in the water-membrane potential differences in the two systems (Pickar & Benz, 1978). However, cation conductance through gramicidin channels spanning these membranes only differs by a factor of 2–3 (Bamberg et al. 1976). Why? It is the pursuit of an answer to this question which led me into my researches in this field.

Type
Research Article
Information
Quarterly Reviews of Biophysics , Volume 25 , Issue 4 , November 1992 , pp. 477 - 510
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Copyright © Cambridge University Press 1992

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