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Extraction and reconstitution of membrane proteins into lipid nanodiscs encased by zwitterionic styrene-maleic amide copolymers.

ABSTRACT: Membrane proteins can be reconstituted in polymer-encased nanodiscs for studies under near-physiological conditions and in the absence of detergents, but traditional styrene-maleic acid copolymers used for this purpose suffer severely from buffer incompatibilities. We have recently introduced zwitterionic styrene-maleic amide copolymers (zSMAs) to overcome this limitation. Here, we compared the extraction and reconstitution of membrane proteins into lipid nanodiscs by a series of zSMAs with different styrene:maleic amide molar ratios, chain sizes, and molecular weight distributions. These copolymers solubilize, stabilize, and support membrane proteins in nanodiscs with different efficiencies depending on both the structure of the copolymers and the membrane proteins.

SUBMITTER: Fiori MC

PROVIDER: S-EPMC7303149 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Extraction and reconstitution of membrane proteins into lipid nanodiscs encased by zwitterionic styrene-maleic amide copolymers.

Fiori Mariana C MC Zheng Wan W Kamilar Elizabeth E Simiyu Geuel G Altenberg Guillermo A GA Liang Hongjun H

Scientific reports 20200618 1

Membrane proteins can be reconstituted in polymer-encased nanodiscs for studies under near-physiological conditions and in the absence of detergents, but traditional styrene-maleic acid copolymers used for this purpose suffer severely from buffer incompatibilities. We have recently introduced zwitterionic styrene-maleic amide copolymers (zSMAs) to overcome this limitation. Here, we compared the extraction and reconstitution of membrane proteins into lipid nanodiscs by a series of zSMAs with diff ...[more]

PMID: 32555261

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