5.1, according to the results of electrostatic calculations, and the
appropriate number of Na+ and Cl ions was added to neutralise
the system and reproduce a 20 mM salt concentration. The
structures were put in a rhombic dodecahedron box with periodic
boundary conditions and solvated with TIP3P water molecules. Long-range electrostatic interactions
were treated with the particle-mesh Ewald method with a
grid spacing of 0.12 nm and cutoff of 8 Å. The molecules were submitted to initial energy
minimisation with the steepest descent for 5000 steps followed
by 100 ns NVT and 300 ps NPT equilibration with position
restraints. Production runs were performed for 10 ns with a 2 fs
step. Temperature and pressure coupling were obtained with
the v-rescale and the
Parrinello–Rahman algorithms,
respectively. Visual inspection of the trajectories and model
manipulations were performed with the UCSF Chimera package
(version 1.9)