Evaluation of DIBMA nanoparticles of variable size and anionic lipid content as tools for the structural and functional study of membrane proteins

Autor(en): Voskoboynikova, Natalia 
Margheritis, Eleonora Germana
Kodde, Felix
Rademacher, Malte
Schowe, Maurice
Budke-Gieseking, Annette
Psathaki, Olympia-Ekaterini 
Steinhoff, Heinz-Jurgen 
Cosentino, Katia 
Stichwörter: Amphiphilic maleic acid-containing polymers; Anionic lipids; Biochemistry & Molecular Biology; Biophysics; DIBMALPs; Membrane protein complexes; Model membranes
Erscheinungsdatum: 2021
Herausgeber: ELSEVIER
Volumen: 1863
Ausgabe: 6
Amphiphilic maleic acid-containing polymers allow for the direct extraction of membrane proteins into stable, homogenous, water-soluble copolymer/lipid nanoparticles without the use of detergents. By adjusting the polymer/lipid ratio, the size of the nanoparticles can be tuned at convenience for the incorporation of protein complexes of different size. However, an increase in the size of the lipid nanoparticles may correlate with increased sample heterogeneity, thus hampering their application to spectroscopic and structural techniques where highly homogeneous samples are desirable. In addition, size homogeneity can be affected by low liposome solubilization efficiency by DIBMA, which carries a negative charge, in the presence of high lipid charge density. In this work, we apply biophysical tools to characterize the size and size heterogeneity of large (above 15 nm) lipid nanoparticles encased by the diisobutylene/maleic acid (DIBMA) copolymer at different DIBMA/lipid ratios and percentages of anionic lipids. Importantly, for nanoparticle preparations in the diameter range of 40 nm or below, the size homogeneity of the DIBMA/lipid nanoparticles (DIBMALPs) remains unchanged. In addition, we show that anionic lipids do not affect the production, size and size homogeneity of DIBMALPs. Furthermore, they do not affect the overall lipid dynamics in the membrane, and preserve the functionality of an enclosed membrane protein. This work strengthens the suitability of DIBMALPs as universal, native-like lipid environments for functional studies of membrane proteins and provide useful insight on the suitability of these systems for those structural techniques requiring highly homogeneous sample preparations.
ISSN: 00052736
DOI: 10.1016/j.bbamem.2021.183588

Show full item record

Page view(s)

Last Week
Last month
checked on Apr 24, 2024

Google ScholarTM