Investigation of transmembrane protein fused in lipid bilayer membranes supported on porous silicon

Abstract

This article investigates a device made from a porous silicon structure supporting a lipid bilayer membrane (LBM)fused with Epithelial Sodium Channel protein. The electrochemically-fabricated porous silicon template had pore diameters in the range 0.2~2 µm. Membranes were composed of two synthetic phospholipids: 1,2-diphytanoyl-sn-glycero-3-phosphoserine and 1,2-diphytanoyl-sn-glycero-3-phosphoethanolamine. The LBMwas formed by means of the Langmuir-Blodgett and Langmuir-Schaefer techniques, at a monolayer surface tension of 26 m Nm(-1) in room temperature and on a deionized water subphase, which resulted in an average molecular area of 0.68-0.73 nm(2). Fusion of transmembrane protein was investigated using Atomic Force Microscopy. Initial atomic force microscopy results demonstrate the ability to support lipid bilayers fused with transmembrane proteins across a porous silicon substrate. However, more control of the membrane's surface tension using traditional membrane fusion techniques is required to optimize protein incorporation.

Engineering Lipid Bilayer Membranes for Protein Studies

“…[48,49] demonstrated the same LB/LS technique to create the artificial phospholipid membranes. This technique offers the advantage of tightly packing the lipid molecules, hence resulting in a bilayer membrane that is as strong and tight as possible.…”

“…At low pH, lipid membrane spreading over a planar surface is favorable, regardless of the net charge on the bilayer [49]. The major advantage of using solid supports is to achieve high robustness and stability of the phospholipid bilayer membrane.…”

“…Thus, the author proposes that the use of the Langmuir-Blodgett (LB) technique and LB/LS techniques will provide more control over bilayer deposition that is currently demonstrated in the majority of research presented to date [48,49]. This technique offers the advantage of tightly packing the lipid molecules, hence resulting in a bilayer membrane that is as strong and tight as possible.…”

“…[48,49,159] have chosen to pattern the porous silicon membrane using silicon on insulator (SOI) substrates. They successfully fabricated pores in the range of 0.2–2.0 μm using an electrical fabrication technique, and tested the supported bilayer with and without fused transmembrane proteins.…”

A Barley Efflux Transporter Operates in a Na+-Dependent Manner, as Revealed by a Multidisciplinary Platform

“…The height (1.7 nm) of the protrusions in bilayers was consistent with the modeled size of the sombrero component, which was structurally predicted to extend from the membrane by approximately the same distance. These observations suggested that Bot1 was incorporated in DMPC liposomes essentially uniformly with its N terminus directed to their exterior surface (Supplemental (Sanganna Gari et al, 2013) and of the epithelial sodium channel in a lipid bilayer membrane (Tantawi et al, 2013).…”