Supplementary information : Direct transfer of membrane proteins from bacteria to planar bilayers for rapid screening by single-channel recording : Nature Chemical Biology

A planar bilayer was formed across a 120-m Teflon aperture prior to the start of the video. A glass probe approaches from behind (cis chamber) and passes through the plane of the bilayer into the trans chamber. Because the aperture (which appears elliptical but is circular) is viewed from above at an angle of 45°, the probe initially appears to be thick and conical, however it is approximately 20 m in radius at the tip and tapers slightly outward along the length used. The probe comes into focus only as it passes through the plane of the bilayer; the tip is out of focus when it enters the trans chamber. After the first insertion/withdrawal cycle, a dark region is visible in the center of the bilayer at the spot from which the tip of the probe was withdrawn. We attribute this to a mass of hexadecane and lipid which is shed from the probe surface as it is pulled from the bilayer. Note that the mass rises due to buoyancy and subsequently fuses with the annulus of the planar bilayer. The deposition of this material does not destabilize the membrane. In total, three insertion/withdrawal cycles are shown, the last withdrawal being especially slow to emphasize the ability of the planar bilayer to withstand mechanical perturbation without rupturing. The video is shown in real time.