|
|
| Line 1: |
Line 1: |
| [[Image:2itd.gif|left|200px]] | | {{Seed}} |
| | [[Image:2itd.png|left|200px]] |
|
| |
|
| <!-- | | <!-- |
| Line 9: |
Line 10: |
| {{STRUCTURE_2itd| PDB=2itd | SCENE= }} | | {{STRUCTURE_2itd| PDB=2itd | SCENE= }} |
|
| |
|
| '''Potassium Channel KcsA-Fab complex in Barium Chloride'''
| | ===Potassium Channel KcsA-Fab complex in Barium Chloride=== |
|
| |
|
|
| |
|
| ==Overview==
| | <!-- |
| Thermodynamic measurements of ion binding to the Streptomyces lividans K(+) channel were carried out using isothermal titration calorimetry, whereas atomic structures of ion-bound and ion-free conformations of the channel were characterized by x-ray crystallography. Here we use these assays to show that the ion radius dependence of selectivity stems from the channel's recognition of ion size (i.e., volume) rather than charge density. Ion size recognition is a function of the channel's ability to adopt a very specific conductive structure with larger ions (K(+), Rb(+), Cs(+), and Ba(2+)) bound and not with smaller ions (Na(+), Mg(2+), and Ca(2+)). The formation of the conductive structure involves selectivity filter atoms that are in direct contact with bound ions as well as protein atoms surrounding the selectivity filter up to a distance of 15 A from the ions. We conclude that ion selectivity in a K(+) channel is a property of size-matched ion binding sites created by the protein structure.
| | The line below this paragraph, {{ABSTRACT_PUBMED_17472437}}, adds the Publication Abstract to the page |
| | (as it appears on PubMed at http://www.pubmed.gov), where 17472437 is the PubMed ID number. |
| | --> |
| | {{ABSTRACT_PUBMED_17472437}} |
|
| |
|
| ==About this Structure== | | ==About this Structure== |
| Line 33: |
Line 37: |
| [[Category: Transmembrane]] | | [[Category: Transmembrane]] |
| [[Category: Voltage-gated channel]] | | [[Category: Voltage-gated channel]] |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 07:51:09 2008'' | | |
| | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 13:45:13 2008'' |