Stability and rigidity/flexibility-Two sides of the same coin?

► Knowledge based FoldUnfold predicts the same flexible regions as found by MDFirst. ► MDFirst uses atom contact fluctuations from MD to build graphs of protein structure. ► Rigid cluster hierarchies are different in thermophiles and mesophiles. ► In MD simulations thermophiles are less flexible then their mesophilic homologs. ► Salt bridges in protein core contribute to stability and rigidity of thermophiles.