6UFE

The structure of a potassium selective ion channel at atomic resolution

Summary for 6UFE

• Entry DOI: 10.2210/pdb6ufe/pdb
• Descriptor: Transporter, (4S)-2-METHYL-2,4-PENTANEDIOL, POTASSIUM ION, ... (4 entities in total)
• Functional Keywords: ion channel, potassium ion channel, membrane protein
• Biological source: Bacillus cereus
• Total number of polymer chains: 2
• Total formula weight: 21886.43

Authors

Langan, P.S.,Vandavasi, V.G.,Sullivan, B.,Afonine, P.V.,Weiss, K.L. (deposition date: 2019-09-24, release date: 2020-08-05, Last modification date: 2023-10-11)

Primary citation

Langan, P.S.,Vandavasi, V.G.,Kopec, W.,Sullivan, B.,Afonne, P.V.,Weiss, K.L.,de Groot, B.L.,Coates, L.
The structure of a potassium-selective ion channel reveals a hydrophobic gate regulating ion permeation.
Iucrj, 7:835-843, 2020

PubMed Abstract: Protein dynamics are essential to function. One example of this is the various gating mechanisms within ion channels, which are transmembrane proteins that act as gateways into the cell. Typical ion channels switch between an open and closed state via a conformational transition which is often triggered by an external stimulus, such as ligand binding or pH and voltage differences. The atomic resolution structure of a potassium-selective ion channel named NaK2K has allowed us to observe that a hydro-phobic residue at the bottom of the selectivity filter, Phe92, appears in dual conformations. One of the two conformations of Phe92 restricts the diameter of the exit pore around the selectivity filter, limiting ion flow through the channel, while the other conformation of Phe92 provides a larger-diameter exit pore from the selectivity filter. Thus, it can be concluded that Phe92 acts as a hydro-phobic gate, regulating the flow of ions through the selectivity filter.

PubMed: 32939275
DOI: 10.1107/S2052252520008271

Experimental method

X-RAY DIFFRACTION (1.2 Å)