Advancing MP1, a novel depolymerase for perpetual cradle-to-cradle plastics recycling

**问题**塑料包装，特别是塑料薄膜，会给回收商带来巨大的挑战。这是一个主要问题，因为它经常是共层压的，含有添加剂，并且受到污染。它还会损坏分类机器。在英国(和大多数发达国家)，塑料薄膜的广泛收集和再加工是有限的；只有10%的英国地方当局接受所有类型的塑料薄膜回收，因此它经常到达垃圾填埋场。在英国，2017年使用了120万吨塑料薄膜。根据目前的收集率，这表明在英国，每年有大量的塑料薄膜被运往垃圾填埋场。**机会**Mellizyme已经发现了一种新型酶‘MP1’，它可以降解塑料薄膜中常用的某些键，从而释放小分子。标准的物理化学回收方法会导致塑料在两轮回收之间损失质量。当降解到无法重复利用时，这会产生垃圾，用于焚烧(产生二氧化碳)或垃圾填埋(这可能会将化学物质浸入环境中)。MP1克服了这个问题，因为塑料薄膜聚合物的生物降解保持了释放的小分子的完整性。这支持了从摇篮到摇篮的永续回收。MP1有巨大的市场机会；在全球范围内，2015年生产的78.2亿吨塑料中只有9%被回收，这表明回收商有很大的机会对原本将被用作垃圾填埋或焚烧的塑料进行定价。**关键项目目标**将Mellizyme技术从TRL3成熟到TRL5\。该项目的成果对于随后的工业规模演示至关重要。**创新**当前最先进的方法：*可以解构多层塑料薄膜，但这需要能量和化学密集型溶剂定向回收和沉淀。*几种微生物可以降解一些塑料，但这似乎只是低分子量成分，而不是长链聚合物骨架。*从树上提取的一种酶显示出对塑料树脂的活性，但反应混合物需要三氮唑的补充。MP1比最先进的：*MP1在不同塑料“家族”中的许多塑料类型中都有活性。*MP1不需要任何苛刻的化学溶剂作为反应的佐剂。*MP1类型的酶速度快，有周转次数。1,000^S-1(相比之下，最好的降解酯PET的酶的周转数只有1.2^S-1)。

**PROBLEM**Plastic packaging, and in particular plastic film, can pose significant challenges to recyclers. It is a major problem as it is often co-laminated, containing additives, and contaminated. It can also damage sorting machinery.The widespread collection and reprocessing of plastic film in the UK (and in most developed countries) is limited; just 10% of local authorities in the UK accept all types of plastic film for recycling, thus it frequently reaches landfill.In the UK, 1.2 million tonnes of plastic film were used in 2017\. Based on current collection rates, this suggests that significant amounts of plastic film reach landfill each year in the UK.**OPPORTUNITY**Mellizyme have identified a novel enzyme 'MP1' that can degrade certain bonds within plastics commonly used in plastic films to liberate small molecules.Standard physico-chemical recycling methods leads to loss of plastic quality between recycling rounds. When degraded beyond re-use, this the creates waste for incineration (generating CO2) or landfill (which can leach chemicals into the environment).This is problem is overcome by MP1, as the biological degradation of the plastic film polymers maintains integrity of the small molecules liberated. This supports perpetual cradle-to-cradle recycling.There is significant market opportunity for MP1; globally, just 9% of the 7.82Bn tons of plastic produced in 2015 was recycled, suggestive of a significant opportunity for recyclers to valorise plastics that would be otherwise destined for landfill or incineration.**KEY PROJECT OBJECTIVES**Maturation of Mellizyme technology from TRL3 to TRL5\. The project outputs are critical for subsequent industrial-scale demonstration.**INNOVATIONS**Current state-of-the-art approaches:* Multilayer plastic films can be deconstructed, but this requires energy and chemical-intensive solvent-targeted recovery and precipitation.* Several microbes can degrade some plastics, but this appears to be only of low molecular weight components, rather than the long-chain polymer backbones.* An enzyme isolated from a tree has demonstrated activity against plastic resins, but the reaction mixture requires triazole supplementation.MP1 improvements over this state-of-the-art:* MP1 has activity across many plastic types within different 'families' of plastics.* MP1 does not require any harsh chemical solvents to be used as adjuvants to the reaction.* MP1-type enzymes are fast, with turnover numbers \>1000^s-1 (for comparison, the best enzyme that degrades the ester PET has a turnover number of just 1.2^s-1).