Hyperthermophile Protein Stabilized under Kinetic Control.

The chemical and thermal unfolding of pyrrolidone carboxyl peptidase from hyperthermophile (PfPCP) is completely reversible with drastically slow unfolding and refolding rates. The higher thermodynamic stability of the hyperthermophile protein compared to homologous protein from mesophile is characterized by the unusually slow unfolding rate. It is revealed that the stability of the hyperthermophile protein is under kinetic control.