Pepsin, Rhizopus inhibitors

Free Energy Calculations on Enzyme-Inhibitor Complexes Studies of Thermolysin and Rhizopus Pepsin... 

The mutation of the hydroxyl group positioned in R-configuration at the C(3) atom of the central statine (rSta) residue of the inhibitor gives rise to AAGbind of -0.51 kcal/mol, which is very close to the experimental value of -0.8 kcal/mol. It may be noted here that the starting configuration of the inhibitor in the enzyme-inhibitor complex is the same as that of pepstatin. The crystal structure of rhizopus pepsin or any other aspartic proteinase... 

K. Suguna, E. A. Padlan, R. Bott, J. Boger, K. D. Parris, and D. R. Davies, Structures of complexes of rhizopus pepsin with pepstatin and other statine-containing inhibitors, Proteins 13 195 (1992). 

In an FEP study, Rao and Singh used AMBER 3.3 to determine the relative binding free enei of pepstatin and its derivatives to Rhizopus pepsin. A united-atom and an all-atom representation were used for the residues of the enzyme and for the inhibitors, respectively. The pepstatin-Rhizopus pepsin complex was modeled starting from the high resolution crystal structure, where the inhibitor was in the reduced form. All pepstatin derivatives studied had modifications made on statine. The AAGlfia mutation of... 

M. R. Reddy, unpublished work, 1999. Calculation of Relative Solvation and Binding Free Energies of Inhibitors to Rhizopus Pepsin. 

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