Each system was energy minimized, heated, and equilibrated in multiple steps. Conjugate-gradient energy minimizations were performed with FA headgroups harmonically restrained first at 100 kcal/mol Å 2 and then 10 kcal/mol Å 2 for 15,000 cycles each. The systems were heated from 23 K to 298.15 K in increments of 25 K for 100 ps each at a 2-fs timestep. Finally, the systems were equilibrated at 298.15 K by slowly releasing harmonic restraints on the lipid headgroups over 500 ps. Production runs were carried out with an NVT ensemble over 500 ns for each system and extended to 1 𝜇s in total for the A1 and C3 replicates. For all procedures, particle-mesh Ewald 106 electrostatics were employed for long-range electrostatic interactions; non-bonded van der Waals interactions and short-range electrostatics were calculated with a 12 Å cut-off. The SHAKE 107 algorithm was used to fix hydrogen bond lengths and a Langevin thermostat with a damping coefficient of 5/ps was applied to maintain temperature control at 298.15 K. Table details the atom counts for each system, as well as the total time simulated for each replicate.