Discovery, Evolution, and Application of Rubber Oxygenases

 

Project Investigators:

Prof. Dr. Martin Weissenborn
MLU, Organic Chemistry

Dr. Mehdi D. Davari
IPB, Computational Chemistry

Prof. Dr. Markus Pietzsch
MLU, Pharmaceutical Technology and Biopharmaceutics

Prof. Dr. Wolfgang Binder
MLU, Macromolecular Chemistry

Project summary:
Polyisoprene is ubiquitously applied in the industry as motor mounts, pipe gaskets, sporting equipment, and many other molded and mechanical goods. Despite this widespread use, degrading polyolefins represents a major challenge due to the lack of hydrolyzable functional groups in the polymer backbone. Nature has evolved an enzyme family, the rubber oxygenases, degrading polyisoprenes via an oxidative breakdown of the polyisoprene backbone. (1) We aim to discover new rubber oxygenases by a computational approach. (2) We will simultaneously focus on the synthesis and purification of highly defined polyisoprenes. These polymers are engineered to have precise sizes and are highly defined. This precision in the polymer substrate allows for the rapid screening of enzymatic degradation using Gas Chromatography (GC) or Ultra-Performance Liquid Chromatography (UPLC). (3) The setup from work package 2 will enable a directed evolution approach, with a primary focus on enhancing enzymatic activity and toluene resistance. Results, whether favorable or not, will be channeled into a machine-learning algorithm to extract essential insights, guiding the team toward optimal enzyme design and performance. To assess the real-world applicability of the best-performing enzyme variants, they will be tested on precisely defined rubber particles. (4) Enzyme production will be scaled up to a level exceeding 100 mg. This larger-scale production will enable the degradation of polyisoprene and significantly contribute to our understanding of sustainable rubber waste management.