Electronic Thesis and Dissertation Repository

Identification and Characterization of Novel Mycotoxin Degrading Enzymes

Kyle N. Hendricks, Western University

Abstract

Plant pathogenic fungi throughout the agricultural supply chain produce mycotoxins, which are harmful secondary metabolites that aid fungal colonization and contaminate food and feed. Consuming mycotoxin-contaminated products poses health risks to humans and animals. While several strategies to limit mycotoxin contamination exist, enzymatic biotransformation of mycotoxins into non-toxic forms offers a potentially safe, specific, and robust solution to manage mycotoxins. To identify novel mycotoxin degradation activities, an in-house developed discovery-based pipeline was employed to culture various mixed microbial communities with mycotoxins. Using the pipeline, a novel thermophilic bacterium that degrades Ochratoxin A was discovered. Additionally, a zearalenone hydrolase previously identified with the pipeline was biochemically characterized and demonstrated to hydrolyze additional resorcylic acid lactones beyond zearalenone, including radicicol. Radicicol inhibits the activity of Heat Shock Protein 90, however following enzymatic treatment, this activity was significantly attenuated. Identifying mycotoxin degradation activity supports continued agricultural production while preserving economic and health interests.