• Nanion Technologies: Smart Tools for Ion Channel Research

    Nanion Technologies: Smart Tools for Ion Channel Research

  • SyncroPatch 384i: HTS Automated Patch Clamp

    SyncroPatch 384i: HTS Automated Patch Clamp

  • SURFE²R 96SE: Label-free HTS Transporter Screening

    SURFE²R 96SE: Label-free HTS Transporter Screening

  • Dynamic Clamp: Patchliner

    Dynamic Clamp: Patchliner

  • Bilayer recordings: Orbit product family

    Bilayer recordings: Orbit product family

  • CardioExcyte 96 SOL: Pacing Cardiomyocytes with Light

    CardioExcyte 96 SOL: Pacing Cardiomyocytes with Light

Our Product Portfolio

SyncroPatch 384

SyncroPatch 384

Patchliner

Patchliner

Port-a-Patch

Port-a-Patch

Port-a-Patch mini

Port-a-Patch mini

CardioExcyte 96

CardioExcyte 96

FLEXcyte 96

FLEXcyte 96

SURFE²R 96SE

SURFE²R 96SE

SURFE²R N1

SURFE²R N1

Orbit 16 TC

Orbit 16 TC

Orbit Mini

Orbit Mini

Vesicle Prep Pro

Vesicle Prep Pro

Buffer Solution

Buffer Solution

2021 - Structural basis for Potassium transport by KdpFABC

 Icon N1  SURFE2R N1 pre-print in bioRxiv (2021)

Authors:

Sweet M.E., Larsen C., Zhang X., Schlame M., Pedersen B.P., Stokes D.L.

Journal:

bioRxiv (2021) doi: 10.1101/2021.01.09.426067


Abstract: 

KdpFABC is an oligomeric K+ transport complex in prokaryotes that maintains ionic homeostasis under stress conditions. The complex comprises a channel-like subunit (KdpA) from the Superfamily of K+ Transporters and a pump-like subunit (KdpB) from the superfamily of P-type ATPases. Recent structural work has defined the architecture and generated contradictory hypotheses for the transport mechanism. Here, we use substrate analogs to stabilize four key intermediates in the reaction cycle and determine the corresponding structures by cryo-EM. We find that KdpB undergoes conformational changes consistent with other representatives from the P-type superfamily, whereas KdpA, KdpC and KdpF remain static. We observe a series of spherical densities that we assign as K+ or water and which define a pathway for K+ transport. This pathway runs through an intramembrane tunnel in KdpA and delivers ions to sites in the membrane domain of KdpB. Our structures suggest a mechanism where ATP hydrolysis is coupled to K+ transfer between alternative sites in the membrane domain of KdpB, ultimately reaching a low-affinity site where a water-filled pathway allows release of K+ to the cytoplasm.


Download here

Back to Overview

We use cookies on our website. Some of them are essential for the operation of the site, while others help us to improve this site and the user experience (tracking cookies). You can decide for yourself whether you want to allow cookies or not. Please note that if you reject them, you may not be able to use all the functionalities of the site.