SBIR Phase I: Enzymes for Accelerated Plastic Recycling

这项小企业创新研究（SBIR）第一阶段项目的广泛影响是使塑料回收过程更高效、更有利可图、更可持续。在美国，目前只有不到10%的塑料被回收利用，其余的被焚烧（15%）或被填埋（75%）。从现在到2050年，全球塑料生产和焚烧产生的碳排放量可能达到560亿吨，占全球温室气体排放量的15%。常规塑料回收的经济性较差，因为在回收过程中使用的高温会导致质量下降，从而大大降低了经济价值。该项目开发了一个低温系统，用于高质量，高价值的塑料产品的闭环回收。拟议中的项目将应用合成生物学和相关生物技术来识别、设计和优化新的酶和酶混合物，以分解聚乙烯（PE）和聚对苯二甲酸乙二醇酯（PET）塑料。这些酶将使闭环塑料回收在经济上可行，低温，低二氧化碳排放的过程。第一个目标是对塑料污染环境中的天然酶进行采样，这些酶已经进化到可以解聚PE和PET合成聚合物。候选PE和PET酶将在可扩展的工艺条件下加速其有效靶向和切割复杂PE和PET聚合物的能力。使用合成生物学、高通量筛选和机器学习技术，将构建、测试和分析数百万种酶变体。这项工作的主要目标是证明与自然发生的塑料降解蛋白相比，PE和PET的解聚速率增加了10倍。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact of this Small Business Innovation Research (SBIR) Phase I project is to enable a more efficient, profitable, and sustainable plastic recycling process. In the United States less than 10% of plastics are currently recycled, and the remainder are incinerated (15%) or placed in landfills (75%). Emissions from global plastics production and incineration could reach 56 billion tons of carbon between now and 2050, accounting for 15% of global greenhouse gas emissions. The economics of conventional plastic recycling are poor, because the high temperatures used in recycling cause quality degradation that greatly reduces the economic value. This project develops a low-temperature system for high quality, high-value plastic products in closed-loop recycling.The proposed project will apply synthetic biology and related biotechnologies to identify, engineer, and optimize new enzymes and enzyme cocktails to break down polyethylene (PE) and polyethylene terephthalate (PET) plastics. These enzymes will enable closed-loop plastic recycling in an economically viable, low temperature, low CO2 emission process. The first objective is to sample plastic contaminated environments for naturally occurring enzymes that have evolved to depolymerize PE and PET synthetic polymers. Candidate PE and PET enzymes will be engineered to accelerate their ability to efficiently target and cut complex PE and PET polymers under scalable process conditions. Millions of enzyme variants will be constructed, tested, and analyzed using synthetic biology, high-throughput screening, and machine learning technologies. A primary goal of this effort is to demonstrate a 10-fold increase in PE and PET depolymerization rates compared to naturally occurring plastic degradation proteins.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.