• Nanion Technologies: イオンチャネル研究のスマートツール

    Nanion Technologies: イオンチャネル研究のスマートツール

  • SyncroPatch 384i: HTS Automated Patch Clamp

    SyncroPatch 384i: HTS Automated Patch Clamp

  • SURFE²R 96SE: ラベルフリーのトランスポーターHTS

    SURFE²R 96SE: ラベルフリーのトランスポーターHTS

  • Dynamic Clamp: Patchliner

    Dynamic Clamp: Patchliner

  • 脂質二分子膜実験: Orbitシリーズ

    脂質二分子膜実験: Orbitシリーズ

  • CardioExcyte 96 SOL: 心筋の光ペーシング

    CardioExcyte 96 SOL: 心筋の光ペーシング

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

2018 - Powering the ABC multidrug exporter LmrA: How nucleotides embrace the ion-motive force

icon pap   Port-a-Patch publication in Science Advances (2018)

Authors:
Agboh K., Lau C.H.F., Khoo Y.S.K., Singh H., Raturi S., Nair A.V., Howard J., Chiapello M., Feret R., Deery M.J., Murakami S., van Veen H.W.

Journal:
Science Advances (2018) 4(9):eaas9365   doi: 10.1126/sciadv.aas9365


Abstract:

LmrA is a bacterial ATP-binding cassette (ABC) multidrug exporter that uses metabolic energy to transport ions, cytotoxic drugs, and lipids. Voltage clamping in a Port-a-Patch was used to monitor electrical currents associated with the transport of monovalent cationic HEPES+ by single-LmrA transporters and ensembles of transporters. In these experiments, one proton and one chloride ion are effluxed together with each HEPES+ ion out of the inner compartment, whereas two sodium ions are transported into this compartment. Consequently, the sodium-motive force (interior negative and low) can drive this electrogenic ion exchange mechanism in cells under physiological conditions. The same mechanism is also relevant for the efflux of monovalent cationic ethidium, a typical multidrug transporter substrate. Studies in the presence of Mg-ATP (adenosine 5′-triphosphate) show that ion-coupled HEPES+ transport is associated with ATP-bound LmrA, whereas ion-coupled ethidium transport requires ATP binding and hydrolysis. HEPES+ is highly soluble in a water-based environment, whereas ethidium has a strong preference for residence in the water-repelling plasma membrane. We conclude that the mechanism of the ABC transporter LmrA is fundamentally related to that of an ion antiporter that uses extra steps (ATP binding and hydrolysis) to retrieve and transport membrane-soluble substrates from the phospholipid bilayer.


Download here

Back

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.