Insight into thermally induced structural changes of lupin seed γ-conglutin

A multidimensional analysis aimed to determine the thermal impact on ?-conglutin at the two oligomeric states was carried out. A wide range of biophysical and bioinformatic methods allowed to get insight into a thermal unfolding mechanism. The determined midpoint transition temperature (Tm) values were remarkably different, being 56.5 ?C and 71.1 ?C for ?-conglutin monomer and hexamer, respectively. The unfolding pattern for hexamer molecules included aggregation/precipitation, while monomers tended to form soluble aggregates after heat exposure. Interestingly, differences in the aromatic amino acid residues movements indicate that during thermal treatment of ?-conglutin hexamer red-shift occurred contrary to the monomer in the case of which blueshift was noted. The obtained results provide an essential contribution to expand our knowledge about the molecular characterization of this intriguing lupin seed protein.