Scientists engineer enzymes to turn crops into recyclable bioplastics

Researchers at Purdue University, supported by a $7 million grant from the U.S. National Science Foundation, are engineering novel enzymes to convert crops like corn and sugar, as well as agricultural waste, into recyclable bioplastics called polyhydroxyalkanoates (PHAs). These bioplastics aim to match the toughness and malleability of conventional petroleum-based plastics while being biodegradable and infinitely recyclable. By using domestically sourced feedstocks, the project also seeks to reduce reliance on imported petrochemicals and strengthen U.S. supply chains. The team is focusing on overcoming the limitations of PHAs, which historically have been fragile and unstable at high temperatures, restricting their use in consumer and medical products. The approach involves tuning the chemical structure of PHAs to enhance their strength and thermal stability through biocatalysis—using engineered enzymes to drive specific chemical reactions efficiently and sustainably. Collaborators from several universities are contributing expertise in enzyme selection, engineering via deep learning, functional testing, and commercialization potential.