MD simulation protocol. MD simulations were performed using pmemd.cuda from AmberTools 19 toolkit . Periodic boundary conditions were applied for the simulations systems. The SHAKE algorithm 106 was applied to all hydrogenheavy atom bonds and SETTLE for bonds belonging to water molecules 107 , and an integration time-step of 2 fs was used for all simulations. Long-range electrostatic interactions were computed with Particle Mesh Ewald summation method 108 with a cutoff of 12 Å. Prior to running the MD simulations, water positions were optimized while keeping the protein constraints with 100 kcal/mol/Å 2 force constant, and energies minimized with 1000 steps of Conjugate Gradient (CG), then gradually heated up to 600 K over 46 ps, followed by 250 steps of CG, then heated again to 300 K over 50 ps. Following the GIST protocol, 2.5 kcal/mol/Å 2 restraints were applied on the protein heavy atoms to prevent the protein to translate and rotate during the simulation, interfering with the volume discretization. Same restraints were applied to counter-ions to prevent them moving into the binding site and generate artefacts during the GIST analysis.