Tunable DNA-Stabilized Bicelles as Nanoscale Membrane Mimetic Systems.

Abstract

Membrane proteins are central to cellular function and constitute the majority of drug targets, yet their structural and functional characterization at the single-molecule level requires stabilization within a native-like lipid environment. Here, we introduce a robust and tunable DNA origami nanodisc that incorporates inherently planar lipid bicelles as a promising platform for future membrane protein studies. The highly charged and bulky DNA envelope acts as a structural stabilizer, enabling efficient bicelle incorporation and stabilization. Moreover, bilayer geometry can be precisely tuned by adjusting the long-chain to short-chain lipid ratio (q-ratio), yielding diameters from ∼18 to 26 nm. As a proof of concept, we demonstrate the successful association of Fragaceatoxin C (FraC) monomers, a pore-forming membrane protein, with the DNA-stabilized bicelles. Potential applications of this versatile platform include high-throughput membrane protein analysis, hydrophobic drug delivery, and hybrid nanopore sensing.