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

**挑战：**尼龙-6,6是由己二酸（ADP）和六亚甲二胺（HMDA）单体通过能源密集型工业过程酯化生产的（每吨尼龙-6,6生产消耗80-60 MJ）。每年全球尼龙-6,6生产释放约1200万吨二氧化碳和约200万吨氧化亚氮（NOx）。世界上75%的ADP用于尼龙-6,6\。ADP生产本身就存在很大的问题：* ~1%的全球氮氧化物排放和0.2%的二氧化碳排放是由ADP生产造成的。*苯是一种不可再生的石油化合物和挥发性致癌物。*废金属催化剂产生有毒废物流。*制造ADP所需的高温和高压每吨ADP消耗100-120 GJ能量。尼龙-6,6可以机械回收，但回收的材料可能含有杂质，并且不像原始尼龙-6,6聚合物那样坚固。尼龙6,6的化学回收可以产生更高质量的再制造产品。然而，现有的化学回收方法比机械回收更复杂，更昂贵。此外，尼龙6,6的化学回收需要有害和有毒的化学佐剂。改进尼龙6,6回收方法的需求尚未得到满足，减少了对尼龙6,6的需求，减少了对ADP和HMDA单体的需求。**创新：** Epoch Biodesign（原Mellizyme Biotechnology）最近纯化了一种代号为“DAM-2”的尼龙水解酶。迄今为止的实验室工作表明，DAM-2可以在室温和常压下催化尼龙6,6的解聚，这代表了目前尼龙6,6回收工艺的重大创新。**项目重点：** Epoch将使用专有的合成生物学工具和方法来提高DAM-2\的活性。他们还将制定从DAM-2介导的解聚合反应的降解产物中挤出新的尼龙6,6长丝的方案。通过完成这项工作，Epoch将为尼龙6,6回收创造一个“改变游戏规则”和“颠覆性”的新能力，从而以环保的方式实现从摇篮到摇篮的回收。

**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.