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Detailed Examination of a Single Conduction Event in a Potassium Channel.

ABSTRACT: Although extensively studied, it has proved difficult to describe in detail how potassium ion channels conduct cations and water. We present a computational study that, by using stratified umbrella sampling, examines nearly an entire conduction event of the Kv1.2/2.1 paddle chimera and thereby identifies the expected stable configurations of ions and waters in the selectivity filter of the channel. We describe in detail the motions of the ions and waters during a conduction event, focusing on how waters and ions enter the filter, the rotation of water molecules inside the filter, and how potassium ions are coordinated as they move from a water to a protein environment. Finally, we analyze the small conformational changes undergone by the protein, showing that the stable configurations are most similar to the experimental crystal structure.

SUBMITTER: Fowler PW

PROVIDER: S-EPMC3797101 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Detailed Examination of a Single Conduction Event in a Potassium Channel.

Fowler Philip W PW Beckstein Oliver O Abad Enrique E Sansom Mark S P MS

The journal of physical chemistry letters 20130829 18

Although extensively studied, it has proved difficult to describe in detail how potassium ion channels conduct cations and water. We present a computational study that, by using stratified umbrella sampling, examines nearly an entire conduction event of the Kv1.2/2.1 paddle chimera and thereby identifies the expected stable configurations of ions and waters in the selectivity filter of the channel. We describe in detail the motions of the ions and waters during a conduction event, focusing on ho ...[more]

PMID: 24143269

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