DAM-2: A novel enzyme for Nylon-6,6 recycling

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**Challenge:** Nylon-6,6 is produced by the esterification of adipic acid (ADP) and hexamethylenediamine (HMDA) monomers via energy intensive industrial processes (consuming between 80-60 MJ per tonne Nylon-6,6 manufactured). Annual global Nylon-6,6 manufacturing releases ~12 million tonne CO2 and ~2 million tonnes of nitrous oxide (NOx).75% of the world's ADP is used for Nylon-6,6\. ADP manufacturing is itself highly problematic:* ~1% of global NOx emissions and 0.2% of CO2 emissions are caused by ADP production.* The benzene feedstock is a non-renewable petroleum compound and volatile carcinogen.* Spent metal catalysts create toxic waste streams.* The high temperatures and pressure required for ADP manufacture consume 100-120 GJ energy per tonne of ADP manufactured.Nylon-6,6 can be recycled mechanically, but the recycled material can contain impurities and is not as a strong as virgin Nylon-6,6 polymer.Chemical recycling of Nylon-6,6 can generate a higher quality of remanufactured product. However, the chemical recycling methods available are more complex and more expensive than mechanical recycling. Moreover, chemical recycling of Nylon-6,6 requires harmful and toxic chemical adjuvants.There is an **unmet need** for improved Nylon-6,6 recycling methods, reducing demand for virgin Nylon-6,6 and reducing demand for ADP and HMDA monomers.**Innovation:** Epoch Biodesign (formerly Mellizyme Biotechnology) recently purified a nylon hydrolase codenamed 'DAM-2'. Laboratory **work-to-date** shows DAM-2 can catalyse the depolymerization of Nylon-6,6 at room temperature and atmospheric pressure -- representing significant innovation in the processes currently available for Nylon-6,6 recycling.**Project focus:** Epoch will use proprietary synthetic biology tools and approaches to improve the activity of DAM-2\. They will also generate protocols for extruding new Nylon-6,6 filament from the degradation products of the DAM-2 mediated depolymerisation reaction.By completing this work Epoch will create a **game-changing** and **disruptive** new capability for Nylon-6,6 recycling, which enables cradle-to-cradle recycling in an environmentally-friendly manner.