Cookies

We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.


Durham Research Online
You are in:

Sub-nanometre mapping of the aquaporin-water interface with multifrequency atomic force microscopy.

Ricci, M. and Quinlan, R. A. and Voïtchovsky, K. (2017) 'Sub-nanometre mapping of the aquaporin-water interface with multifrequency atomic force microscopy.', Soft matter., 13 (1). pp. 187-195.

Abstract

Aquaporins are integral membrane proteins that regulate the transport of water and small molecules in and out of the cell. In eye lens tissue, circulation of water, ions and metabolites is ensured by a microcirculation system in which aquaporin-0 (AQP0) plays a central role. AQP0 allows water to flow beyond the diffiusion limit through lens membranes where it naturally arranges in a square lattice. Malfunction of AQP0 is related to numerous deseases such as cataract. Despite considerable research into its structure, function and dyanmics, the interface between the protein and the surrounding liquid and the effect of the lattice arrangement on the behaviour of water at the interface with the membrane are still not fully understood. Here we use a multifrequency atomic force microscopy (AFM) approach to map both the liquid at the interface with AQP0 and the protein itself with sub-nanometer resolution. Imaging using the fundamental eigenmode of the AFM cantilever probes mainly the interfacial water at the surface of the membrane. Results highlight a well-defined region that surrounds AQP0 tetramers and where water exhibits a higher affinity for the protein. Imaging at the second eigenmode is dominated by the mechanical response of the protein and provides sub-molecular details of the protein surface and sub-surface structure. The relationship between modes and harmonics is also examined.

Item Type:Article
Full text:(AM) Accepted Manuscript
Available under License - Creative Commons Attribution.
Download PDF
(1252Kb)
Full text:(VoR) Version of Record
Available under License - Creative Commons Attribution.
Download PDF (Advance online version)
(3066Kb)
Full text:(VoR) Version of Record
Available under License - Creative Commons Attribution.
Download PDF (Final published version)
(3072Kb)
Status:Peer-reviewed
Publisher Web site:http://dx.doi.org/10.1039/C6SM00751A
Publisher statement:This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Date accepted:15 June 2016
Date deposited:29 June 2016
Date of first online publication:16 June 2016
Date first made open access:05 July 2016

Save or Share this output

Export:
Export
Look up in GoogleScholar