The membrane fluidity, gauged by Dxy (Figure ) and RCF decay (Figure of SI), constantly decreases with decreasing temperature. These suggest an absence of fluid-to-gel phase transition within the temperature range. Notably, the values for both NM and MMU almost coincide with each other at all temperatures. Therefore, the CG model is unable to distinguish between NM and MMU membranes and therefore the purpose of cyclopropanation is not clear.