Abstrakt

Transfer Thermodynamics Of Some Amino Acids In A Protein Stabilizing And A Denaturant Media

I.Basumallick, Someswar Chatterjee

A comparative study on transfer free energies of some amino acids from water to aqueous urea, a protein-denaturing medium, and water to aqueous glycerol, a protein-stabilizing medium, is presented. Transfer free energies have been dissected into cavity term [ΔG0 t(cav)], electrical term[ΔG0 t(ele)] and interaction term[ΔG0 t(int)]. Interaction term includes all type of interaction like hard soft, hydrogen bond, hydrophobic interaction etc. Calculation of hard soft parameters of these amino acids and co solvents, by semi empirical method using standard soft ware, reveals that this type of hard soft interaction contributes significantly to the ΔG0 t(int).