Biophysical Journal 51: 661-672 (1987)
© 1987 the Biophysical Society

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sung, S S Articles by Jordan, P C Search for Related Content PubMed PubMed Citation Articles by Sung, S S Articles by Jordan, P C

Why is gramicidin valence selective? A theoretical study.

ABSTRACT

Calculations contrasting the channel solvation energy for cesium ions and chloride ions associated with water in gramicidin-like channels are presented. The energy profile for the cation exhibits a deep well at the channel entrance; within the single file region the solvation energy is roughly constant. The anion exhibits a totally different energy profile. There is an energy barrier at the channel entrance; if the ion could surmount this barrier, it would be quite stable within the channel. At the channel entrance, the calculated solvation energy difference between anion and cation is approximately 15 kcal mol-1. This is completely consistent with the observation that chloride neither permeates nor blocks the channel since the estimated rate of ion entry would be approximately 0.01-10(-5) s-1, far slower than the rate at which the channel dimer dissociates into monomers.

This article has been cited by other articles:

				S. Edwards, B. Corry, S. Kuyucak, and S.-H. Chung Continuum Electrostatics Fails to Describe Ion Permeation in the Gramicidin Channel Biophys. J., September 1, 2002; 83(3): 1348 - 1360. [Abstract] [Full Text] [PDF]

				B. Wallace and K Ravikumar The gramicidin pore: crystal structure of a cesium complex Science, July 8, 1988; 241(4862): 182 - 187. [Abstract] [PDF]