Biocatalytic Conversion of 5-Hydroxymethylfurfural by Galactose Oxidase: Toward Scalable Technology Using Integrated Process and Enzyme Engineering

5-Hydroxymethylfurfural (HMF) has emerged as a crucial bio-based chemical building block in the drive towards developing materials from renewable resources, due to its direct preparation from sugars and its readily diversifiable scaffold. A key obstacle in transitioning to bio-based plastic production lies in meeting the necessary industrial production efficiency, particularly in the cost-effective conversion of HMF to valuable intermediates. To address the challenge of developing scalable technology for oxidizing crude HMF to more valuable chemicals, we have integrated process and enzyme engineering to provide a galactose oxidase (GOase) variant with remarkably high activity toward HMF, improved O2 binding and excellent productivity (>1,000,000 TTN). The process concept presented here for GOase catalysed selective oxidation of HMF to 2,5-diformylfuran offers a productive and efficient platform for further development, thereby laying the groundwork for a biocatalytic route to scalable production of furan-based chemical building blocks from sustainable feedstocks.