Putting the Piezolyte Hypothesis under Pressure (Biophysical Journal)

A group of small molecules that stabilize proteins against high hydrostatic pressure has been classified as piezolytes, a subset of stabilizing cosolutes. This distinction would imply that piezolytes counteract the effects of high hydrostatic pressure through effects on the volumetric properties of the protein. The purpose of this study was to determine if cosolutes proposed to be piezolytes have an effect on the volumetric properties of proteins through direct experimental measurements of volume changes upon unfolding of model proteins lysozyme and ribonuclease A, in solutions containing varying cosolute concentrations.