In a context where food industry is on one hand searching for new protein forms to cover the basic world needs and on the other hand constantly developing preservation processes, a deeper knowledge on proteins evolution under pressure and eventually at high pressure is fundamental.  Pressure can modify proteins properties involved in food processing: solubility, gelation, coagulation…

It is well known that pressure, by changing the available volume, impacts the native state of the protein, and that high pressure has been used in many works to follow protein unfolding. Indeed, the multiple interactions involved in the secondary, ternary and quaternary structure evolve under pressure. The compression of the internal cavity also leads to a change in the hydrophilic interactions.

In this work, with focus on some well characterized proteins such as Bovine Serum Albumin and Egg Lysozyme, for which we aim at characterizing the evolution under pressure and eventually high pressures with a particular interest for aggregation processes.  Various evolution steps are expected depending on the experimental conditions, in particular, pressure, holding time, pH, solvent, temperature are expected to influence the evolution.  In this study, we explore some paths of the energy landscape of these proteins under pressures, through experimental characterization tools probing protein structures or properties at different length scales,  either in operando or ex-situ investigations. The results will be discussed in comparison with the aggregation processes observed through temperature treatments (figure 1: aggregation kinetic of Lysozyme (70°C, pH2) probed by thioflavine luminescence).

Funding : Labex NUMEV AAP2018-1