Mixed plastics waste valorization through tandem chemical oxidation and biological funneling

• DOI: 10.1126/science.abo4626
• Publication Date: 2022-10-13T17:57:25Z
• Authors: Kevin P. Sullivan; Allison Z. Werner; Kelsey J. Ramirez; Lucas D. Ellis; Jeremy R. Bussard; Brenna A. Black; David G. Brandner; Felicia Bratti; Bonnie L. Buss; Xueming Dong; Stefan J. Haugen; Morgan A. Ingraham; Mikhail O. Konev; William E. Michener; Joel Miscall; Isabel Pardo; Sean P. Woodworth; Adam M. Guss; Yuriy Román-Leshkov; Shannon S. Stahl; Gregg T. Beckham
• Keywords: 0301 basic medicine; Soil; 03 medical and health sciences; Pseudomonas putida; 13. Climate action; Polyhydroxyalkanoates; Oxidation-Reduction; Plastics; 7. Clean energy; 12. Responsible consumption

Mixed plastics waste represents an abundant and largely untapped feedstock for the production of valuable products. The chemical diversity and complexity of these materials, however, present major barriers to realizing this opportunity. In this work, we show that metal-catalyzed autoxidation depolymerizes comingled polymers into a mixture of oxygenated small molecules that are advantaged substrates for biological conversion. We engineer a robust soil bacterium, Pseudomonas putida , to funnel these oxygenated compounds into a single exemplary chemical product, either β-ketoadipate or polyhydroxyalkanoates. This hybrid process establishes a strategy for the selective conversion of mixed plastics waste into useful chemical products.