The initial coordinates of the SOM structure and calcium ions were obtained by mapping the final output structure of the atomistic simulations to the coarse-grained representation. The structure was solvated, firstly with regular-sized water, and secondly with tiny-sized water, using the GROMACS tool gmx solvate. The number of water beads was chosen so that it corresponded to the same water concentration as in the respective atomistic model. This was done for each of the three different LHA models and for the different water contents, respectively. The equilibration procedures and simulation parameters were the same as for the isolated coarse-grained fragments, except that a time step of 10 fs and a pressure coupling constant of τ p = 12.0 ps were used for all the simulations. Furthermore, the simulation time of the production run was set to 500 ns.