THERMODYNAMIC APPROACH TO THE COMPARATIVE-ANALYSIS OF INTEGRAL HYDROPHOBICITY OF LEGUMIN AND LEGUMIN-T IN NATIVE AND DENATURATED FORMS .1. BROAD BEAN LEGUMIN

The specific integral hydrophobicity of denatured forms of legumin and legumin-T from broad beans was evaluated through their hydration heat capacities. These were calculated as differences between partial heat capacities obtained from differential scanning microcalorimetry data and heat capacities in the gas phase, which were calculated by the use of the method of additive group contributions, taking into account th e expansion of protein molecule in the gas phase. It is shown that the re is no significant difference between the data for denatured forms o f both proteins. The comparative evaluation of the hydration heat capa cities of native forms of legumin and legumin-T was carried out. It is shown that the native legumin-T has a greater value of the hydration heat capacity and respectively is more hydrophobic than the native leg umin. On the basis of the values of differences between the heat capac ities in denatured and native states it is shown that the accessible h ydrophobic surface of the native legumin-T related to a mean amino aci d residue is 8-13 A(2) greater than that of the native legumin.