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Electroneutral polymer nanodiscs enable interference-free probing of membrane proteins in a lipid-bilayer environment

ABSTRACT: Membrane proteins can be examined in near-native lipid-bilayer environments with the advent of polymer-encapsulated nanodiscs. These nanodiscs self-assemble directly from cellular membranes, allowing in vitro probing of membrane proteins with techniques that had previously been restricted to soluble or detergent-solubilized proteins. Nonetheless, the high charge densities of existing polymers obstruct bioanalytical and preparative techniques through unspecific interactions. Here we describe a simple strategy for producing water-soluble, electroneutral polymer nanodiscs. Through attachment of a sulfobetaine group, the commercial polymers DIBMA and SMA can be easily converted into the charge-neutral maleimide derivatives, sulf DIBMA and sulf SMA, which readily extract proteins and phospholipids from artificial and cellular membranes to form nanodiscs. Crucially, the electroneutrality of the new nanodiscs averts unspecific interactions, thereby enabling reliable lab-on-a-chip detection of protein/lipid interactions and in vitro translation of membrane proteins. Finally, we create a library containing thousands of human membrane proteins and use proteome profiling by mass spectrometry to show the preservation of protein complexes in electroneutral nanodiscs.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Fibroblast

SUBMITTER: Markus Räschle

LAB HEAD: Markus Räschle

PROVIDER: PXD030958 | Pride | 2023-01-17

REPOSITORIES: Pride

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