Artículos de revistas
A three-barrier model for the hemocyanin channel
Fecha
1981Registro en:
Journal of General Physiology, Volumen 78, Issue 6, 2018, Pages 657-681
15407748
00221295
10.1085/jgp.78.6.657
Autor
Cecchi, Ximena
Alvarez, Osvaldo
Latorre, Ramón
Institución
Resumen
Keyhole limpet hemocyanin forms ion-conducting channels in planar lipid bilayer membranes. Ionic current through the open hemocyanin channel presents the following characteristics: (a) it is carried mainly by cations; (b) it is a nonlinear function of membrane potential; (c) channel conductance is a saturating function of ion activity; (d) it shows ionic competition. A model for the open hemocyanin channel is developed from absolute reaction rate theory. The model calls for three energy barriers in the channel. Two energy harriers represent the entrance and exit of the ion into and out of the channel. The third barrier separates two energy minima that represent two binding sites. Furthermore, only one ion is allowed inside the channel at a given time. This model is able to recreate all the hemocyanin channel characteristics found experimentally in negatively charged and neutral membranes. © 1981, Rockefeller University Press., All rights reserved.