Perturbed angular correlation experiments on the pressure-induced structural modification of bovine serum albumin

The hydrodynamic behaviour of the bovine serum albumin (BSA) was studied by means of the Perturbed Angular Correlation (PAC) technique as a function of the hydrostatic pressure (up to 4.1 kbar) applied to the sample. The results have clearly shown that at moderated pressures (around 1.5 kbar) the BSA molecule suffers structural modifications which produces an increase of the molecular volume and the rotational correlation time of the molecule. About the reversibility of the process, our results indicate that the changes are fully irreversible. Our experiments are the first devoted to the study of the high-pressure behaviour of biological molecules using the PAC technique.