Fig. 2: Membrane deformation analysis in CG MD simulations.

Membrane bending activity of the S-OPA1 tetramer 1 measured in CG MD simulations with a membrane patch containing 44% POPC, 39% POPE, and 17% CL or POPS. The three graphs correspond to top views of the membranes, color-coded by the replica- and trajectory-averaged (last 4 µs out of 8 µs) deformations along the membrane normal, measured in 1/Å. The images (from left to right) show the CL membrane without protein, the CL membrane with S-OPA1 tetramer, and the POPS membrane with S-OPA1 tetramer. Red and blue colors indicate membrane pulling and pushing in the direction of the membrane normal, respectively. The comparison of the three different membrane deformation analyses indicate that the S-OPA1 tetramer was able to bend membranes containing both CL and POPS, but the extent of deformation is decreased in the presence of POPS (fewer areas of deep blue and deep red). The membrane pulling in POPS-containing membranes peaks at ~0.3 Å⁻¹, while membrane pushing only reaches to −0.2 Å⁻¹ in one region and is even weaker in others. The dashed lines correspond to an overlay of the position of the OPA1 tetramer.