A Bioinspired Glycopolymer for Capturing Membrane Proteins in Native-Like Lipid-Bilayer Nanodiscs

Danielczak, B.; Rasche, M.; Lenz, J.; Perez Patallo, E.; Weyrauch, S.; Mahler, F.; Agbadaola, M. T.; Meister, A.; Babalola, J. O.; Vargas, C.; Kolar, C.; Keller, S.

doi:10.1101/2021.03.31.437849

bioRxiv · 10.1101/2021.03.31.437849

A Bioinspired Glycopolymer for Capturing Membrane Proteins in Native-Like Lipid-Bilayer Nanodiscs

Danielczak, B.·Rasche, M.·Lenz, J.·Perez Patallo, E.·Weyrauch, S.·Mahler, F.·Agbadaola, M. T.·Meister, A.·Babalola, J. O.·Vargas, C.·Kolar, C.·Keller, S.

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Abstract

Amphiphilic copolymers that directly extract membrane proteins and lipids from cellular membranes to form nanodiscs combine the advantages of harsher membrane mimics with those of a native-like membrane environment. Among the few commercial polymers that are capable of forming nanodiscs, alternating diisobutylene/maleic acid (DIBMA) copolymers have gained considerable popularity as gentle and UV-transparent alternatives to aromatic polymers. However, their moderate hydrophobicities and high electric charge densities render all existing aliphatic copolymers rather inefficient under near-physiological conditions. Here, we introduce Glyco-DIBMA, a bioinspired glycopolymer that possesses increased hydrophobicity and reduced charge density but nevertheless retains excellent solubility in aqueous solutions. Glyco-DIBMA outperforms established aliphatic copolymers in that it solubilizes lipid vesicles of various compositions much more efficiently, thereby furnishing smaller, more narrowly distributed nanodiscs that preserve a bilayer architecture and exhibit rapid lipid exchange. We demonstrate the superior performance of Glyco-DIBMA in preparative and analytical applications by extracting a broad range of integral membrane proteins from cellular membranes and further by purifying a membrane-embedded voltage-gated K+ channel, which was fluorescently labeled and analyzed with the aid of microfluidic diffusional sizing (MDS) directly within native-like lipid-bilayer nano-discs.

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Danielczak, B., Rasche, M., Lenz, J., Perez Patallo, E., Weyrauch, S., Mahler, F., Agbadaola, M. T., Meister, A., Babalola, J. O., Vargas, C., Kolar, C., Keller, S.. 2021-04-01. A Bioinspired Glycopolymer for Capturing Membrane Proteins in Native-Like Lipid-Bilayer Nanodiscs. https://doi.org/10.1101/2021.03.31.437849

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