How Ligand Binding Affects the Dynamical Transition Temperature in Proteins.

摘要: The biochemical functions of proteins are activated at the protein glass transition temperature, which has been proposed to be dependent upon protein-water interactions. However, molecular level it is unclear how ligand binding well-defined sites can influence this temperature. We thus report dynamics (MD) simulations ϵ subunit from thermophilic Bacillus PS3 in ATP-free and ligand-bound states over a range temperatures 20 300 K, study association also measure mean square displacement (MSD) each state, well established as means quantify dynamical temperature dependence. find that largely unaffected by association, but MSD beyond increases more rapidly state. Our data suggests ligands effectively "shield" site solvent, hence stabilize domains with increasing