CPOS Seminar: Directed Evolution of a C(sp3)-F Bond Forming Enzyme and Biocatalyzed Controlled Radical Polymerization
Speaker: Betty Chen, PhD Student, Department of Chemistry and Biochemistry, Yang Lab, Read de Alaniz Lab, UC Santa Barbara
Abstract: Biocatalysis has diverse applications in various fields ranging from food industry to drug development. I will introduce our recent work on the development of new biocatalytic processes. The first part of this presentation will focus on engineering a new enzyme to allow for C(sp3)–H fluorination in small-molecule substrates. The second part will discuss biocatalytic controlled radical polymerization.
Organofluorine compounds are versatile in pharmaceutical chemistry, agrochemistry, and polymer chemistry. However, few examples of C–F bond-forming enzymes have been reported. We repurposed a non-heme Fe-dependent enzyme, MthEgtB, to catalyze unnatural C–F fluorination via a radical mechanism. The activity of the enzyme toward fluorination was improved 28-fold through directed evolution. The evolved enzymes also displayed promiscuous anion rebound activities. We are also interested in applying biocatalysis and enzyme engineering to the field of polymer chemistry to address challenging problems. Metalloproteins have been previously exploited to catalyze atom transfer radical polymerization (ATRP). Through the engineering of metalloproteins, we are in the process of developing biocatalysts with enhanced efficiency and selectivity for polymerization processes.
