Protein structure and ionic selectivity in calcium channels: Selectivity filter size, not shape, matters
نویسندگان
چکیده
منابع مشابه
Protein structure and ionic selectivity in calcium channels: selectivity filter size, not shape, matters.
Calcium channels have highly charged selectivity filters (4 COO(-) groups) that attract cations in to balance this charge and minimize free energy, forcing the cations (Na(+) and Ca(2+)) to compete for space in the filter. A reduced model was developed to better understand the mechanism of ion selectivity in calcium channels. The charge/space competition (CSC) mechanism implies that Ca(2+) is m...
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ژورنال
عنوان ژورنال: Biochimica et Biophysica Acta (BBA) - Biomembranes
سال: 2009
ISSN: 0005-2736
DOI: 10.1016/j.bbamem.2009.09.022