Coarse-grained modelling: MD-simulations of the multicomponent membrane systems in AA-resolution is quite challenging because although it reproduces many of the structural properties of the membrane systems, it fails to reproduce the phase behaviour . The major reasons are long simulation time for the mutual diffusion of various constituents (around microsecond ranges) and requirement of a larger system to exactly predict the phase behaviour of a multicomponent bilayer. But due to limited computational performance it is quite impossible to perform the above in AA-resolution. However, there are some alternative pathways to speed up the simulations such as coarse grained (CG) MD simulations which can predict the phase behaviour of a multicomponent bilayer successfully MARTINI-FF is a very well-known CG-model that can correctly predict the phase behaviour or phase separation of a multicomponent membrane system. In MARTINI-FF four atoms in a lipid molecule is considered as one bead and thus it becomes possible to build larger systems and simulate it at longer time scales at low computational cost. However, for considering four atoms as a single bead CG-models are unable to distinguish lipids with 16:0 and 18:0 fatty acid chains. For water molecules we have taken the most commonly used CG-MARTINI water model where one water bead is equivalent to four individual water molecules. In spite of such rough approximation, the dynamical properties (e.g., viscosity, diffusion coefficient) of CG water are in semiquantitative agreement with the experiment . Nonetheless, the freezing temperature of MARTINI-CG water is at around 290 K. Freezing of water at low temperature ranges can induce fluid-to-gel phase transition of the membrane. To prevent such undesiring freezing of water, anti-freeze particles are added (resembling the antifreezing agent). MARTINI forcefield was originally parameterized at room temperature. But now, the MD simulations of realistic cell membranes are performed over a wide range of temperature . The earlier study has captured the temperature dependence of the diffusion and viscosity of MARTINI CG water in good agreement with the TIP4P/2005 water model . Therefore, the MARTINI-CG water model is well enough for the simulation of realistic cell membrane at lower temperatures. The coarse-grained native E. coli membrane (NM) and modified E. coli membranes (MMS and MMU) are parameterised with recently optimised MARTINI 3 forcefield (www.cgmartini.nl).