Application of peroxidases for the synthesis of fine chemicals and drug discovery

Enzyme catalysis is extremely broad based, finding applications in a variety of syntheses. This work examined the use of redox enzymes, specifically, peroxidases, in the synthesis of fine chemicals and in drug discovery. In the first part of the research, the fungal enzyme, chloroperoxidase, was examined as an alternative catalyst for epoxidation of alkenes. The interest stems from the fact that epoxides are used to introduce asymmetry in a variety of pharmaceuticals, and to make chiral synthons. Enzymes offer advantages in mild process conditions and broad substrate specificities over the traditional processes. The results indicate that CPO retains 25% of its native activity in organic media, and can be engineered to possess features requisite to an industrial catalyst.; In the second part of this thesis, enzymatic processes at multiple scales were developed for the synthesis and discovery of bioactive polymers. Both solution and solid phase synthesis techniques were used to study atherosclerosis. In solution phase, screening strategies were developed to identify molecules with optimal activity and to gauge possible structure activity relationships based on the naturally occurring phenol, apocynin, as the lead to generate a class of molecules that are capable of inhibiting, but not completely blocking, the assembly of NADPH oxidase, an enzyme implicated in several pathologies.; Finally, the biologically active phenolic oligomers were synthesized on an array-based solid-phase matrix. This was achieved by first attaching the seed phenol to APTES derivatized glass slides via ester or amide bonds. The oligophenols for screening were then enzymatically generated in a spatially addressable format combinatorially using nanoliter pipetting techniques. This process allowed the elimination of purification steps as products were recovered merely by removing excess reagents. The compounds were screened for biological activity based on their ability to bind to specific peptide sequences critical to the assembly of NADPH oxidase. An alternative scheme was developed, wherein, the peptide target was immobilized onto glass slides, and the bioactive molecules generated in situ using peroxidase catalysis in nL sized droplets. The screening step utilized the disulfide bond formation between two thiol containing peptides; one immobilized, and the other fluorescently tagged, in solution.