THERMODYNAMICS OF ENZYMATIC-SYNTHESIS OF SOLID-PHASE PEPTIDES

The Gibbs free energy changes of the individual and net synthetic equilibrium of solid-phase tert-butyloxycarbonyl-Phe-Gly p-substituted anilides are calculated from the HPLC analysis data for the equilibrium concentrations. A linear free energy relationship is observed for the net synthetic equilibrium and precipitation equilibrium, suggesting that the latter provides the driving force for the chymotryptic synthesis of these insoluble peptides. This conclusion is strongly supported by a linear correlation between the synthetic yield and the square root of the product solubility.