Equilibrium Ion Binding Properties of Potassium-Selective and Non-Selective Cation Channels
نویسندگان
چکیده
منابع مشابه
On the selective ion binding hypothesis for potassium channels.
The mechanism by which K(+) channels select for K(+) over Na(+) ions has been debated for the better part of a century. The prevailing view is that K(+) channels contain highly conserved sites that selectively bind K(+) over Na(+) ions through optimal coordination. We demonstrate that a series of alternating sites within the KcsA channel selectivity filter exists, which are thermodynamically se...
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All living cells are surrounded by a thin, approximately 40 Å thick lipid bilayer called the cell membrane. The cell membrane holds the contents of a cell in one place so that the chemistry of life can occur, but it is a barrier to the movement of certain essential ingredients including the ions Na, K, Ca, and Cl. The barrier to ion flow across the membrane—known as the dielectric barrier—can b...
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ژورنال
عنوان ژورنال: Biophysical Journal
سال: 2014
ISSN: 0006-3495
DOI: 10.1016/j.bpj.2013.11.3031