Limited tryptic hydrolysis of pea legumin: molecular mass and conformational stability of legumin-T

The investigation of hydrodynamic and thermodynamic properties and the dete rmination of the molecular mass of legumin-T, the product of limited trypti c hydrolysis of the 11-S-globulin from pea seeds. was carried out to ascert ain the structural relationship to globulin-T's from other legumin-like pro teins. The obtained legumin-T preparation has a molecular mass M-w = 260 +/ - 10 kDa and M-S,M-D = 270 +/- 20 kDa. The secondary structure of legumin-T is characterised by a high percentage of beta -sheet conformation, compara ble to that of native legumin and a reduced percentage of helical conformat ion. The conformational stability of legumin-T evaluated by equilibrium unf olding in the presence of guanidinium chloride was only slightly reduced in comparison to the native legumin, whereas the calorimetrically determined denaturation enthalpy and Gibbs energy of denaturation were found to be inc reased for legumin-T. These physicochemical properties are very similar to those of faba bean legumin-T. (C) 2001 Elsevier Science B.V. All rights res erved.