The development of low molecular weight dimerization inhibitors of HIV -1 protease

Michael David Shultz, Purdue University

Abstract

A novel strategy for developing low molecular weight inhibitors of enzyme dimerization was accomplished using HIV-1 protease. The strategy involved the study of interactions of the residues in crosslinked, interfacial inhibitors of HIV-1 protease dimerization. The mechanism of inhibition was confirmed using enzyme kinetic techniques, and the activity of various mutants of the starting inhibitor were synthesized and evaluated. The tethering moiety of these agents was altered to enhance binding to the protease enzyme; however, it was determined that the binding of the inhibitor did not occur according to the model proposed. From this information, a new binding model was developed and used in conjunction with previous structure/inhibition studies to devise a plan of rational truncations of the crosslinked peptides in the inhibitor. These agents were tested for their ability to disrupt the quaternary structure of the protease enzyme resulting in the determination of several smaller inhibitors that could partially inhibit protease dimerization. A change in one residue of a truncated inhibitor incapable of disrupting the protease dimer resulted in the restoration of dimerization inhibition. This minimum pharmacaphore was the basis for a focused library of single residue mutations. The library was screened for increased inhibition and changes that resulted in more potent inhibitors were identified and their ability to disrupt the protease dimer was quantified. Using the information gathered from the library of single point mutants, a series of inhibitors with several residues mutated simultaneously was generated. These inhibitors were evaluated and the most potent dimerization inhibitor developed in our lab was identified.

Degree

Ph.D.

Advisors

Chmielewski, Purdue University.

Subject Area

Organic chemistry|Biochemistry

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