7B5P

AcrB in cycloalkane amphipol

Summary for 7B5P

• Entry DOI: 10.2210/pdb7b5p/pdb
• EMDB information: 10182 12043 7074
• Descriptor: Efflux pump membrane transporter (1 entity in total)
• Functional Keywords: drug exporter, membrane protein, amphipol
• Biological source: Escherichia coli
• Total number of polymer chains: 3
• Total formula weight: 341758.43

Authors

Higgins, A.J.,Flynn, A.J.,Muench, S.P. (deposition date: 2020-12-05, release date: 2021-12-08, Last modification date: 2025-07-02)

Primary citation

Higgins, A.J.,Flynn, A.J.,Marconnet, A.,Musgrove, L.J.,Postis, V.L.G.,Lippiat, J.D.,Chung, C.W.,Ceska, T.,Zoonens, M.,Sobott, F.,Muench, S.P.
Cycloalkane-modified amphiphilic polymers provide direct extraction of membrane proteins for CryoEM analysis.
Commun Biol, 4:1337-1337, 2021

PubMed Abstract: Membrane proteins are essential for cellular growth, signalling and homeostasis, making up a large proportion of therapeutic targets. However, the necessity for a solubilising agent to extract them from the membrane creates challenges in their structural and functional study. Although amphipols have been very effective for single-particle electron cryo-microscopy (cryoEM) and mass spectrometry, they rely on initial detergent extraction before exchange into the amphipol environment. Therefore, circumventing this pre-requirement would be a big advantage. Here we use an alternative type of amphipol: a cycloalkane-modified amphiphile polymer (CyclAPol) to extract Escherichia coli AcrB directly from the membrane and demonstrate that the protein can be isolated in a one-step purification with the resultant cryoEM structure achieving 3.2 Å resolution. Together this work shows that cycloalkane amphipols provide a powerful approach for the study of membrane proteins, allowing native extraction and high-resolution structure determination by cryoEM.

PubMed: 34824357
DOI: 10.1038/s42003-021-02834-3

Experimental method

ELECTRON MICROSCOPY (3.2 Å)