Abstract:

Synthetic biology is an interdisciplinary research field, for which complete quantitative research systems have been established in bacteria, yeast, and mammalian cells. However, synthetic biology in plants is still at its infancy. Plant synthetic biology can play important roles in synthesizing plant natural products, developing molecular farming, improving photosynthesis to increase light energy utilization efficiency, designing carbon farming plants, and building plant factories. In the current efforts in creating a carbon neutral society, plant synthetic biology can help to address challenges of food shortage, energy crisis, and environmental pollution. Specifically, innovative methods can be developed to reduce the emission of CO₂ and pollutants through plant production of high value products, whose industrial production is mostly associated with high CO₂ emission. Moreover, plant synthetic biology can be used to optimize plant production through minimizing carbon emissions and reducing the use of chemical fertilizers and pesticides. Furthermore, plants specialized in carbon capturing, such as high photosynthetic efficiency, large root systems, and high resistance to degradation, should be developed as well. Various options for increased photosynthetic efficiency, such as optimizing the antenna size of photosystem, converting C₃ to C₄ photosynthesis, introducing CO₂ concentrating mechanisms, and establishing the photorespiration bypasses into C₃ crops, holds the potential to dramatically increase the carbon capturing capacity for improved productivity. In the future, in addition to crops, trees and algae can also be engineered to become efficient carbon sinks. Photosynthetic algae are expected to become a source of clean energy and industrial production system with zero or negative carbon emissions. In the long term, a complete plant factory system, which has optimal control of light, temperature, CO₂, water, and nutrient, will be developed to achieve optimal plant growth and production while maintaining maximal carbon capturing capacity. Finally, artificial photosynthesis also promises to be an ideal solution as an energy production system. These aspects will be facilitated by the rapid development of plant synthetic biology tools, including biological part standardization, genetic circuits design, and directed evolution. This paper summarizes the major progresses of plant synthetic biology and prospects the major roles of plant synthetic biology in the future efforts in carbon emission peak and carbon neutrality.

Key words: plant synthetic biology, carbon emission peak, carbon neutrality, natural product, photosynthesis, molecular farming, carbon farming, plant factory

摘要：

合成生物学是一门包括生物学、数学、物理学、化学、工程及信息科学等多学科交叉的前沿学科。历经多年发展，目前在细菌、酵母等微生物和哺乳动物细胞底盘中已初步形成了完备的定量化研究体系，然而植物合成生物学依然处于起步阶段。植物合成生物学可在挖掘植物次生代谢天然产物、生产分子农业制品、提升光合作用光能利用效率、创制碳汇植物和建立植物工厂系统等方面发挥作用。特别是在当前面向碳达峰与碳中和过程中，植物合成生物学可以参与解决人类活动所面临的粮食短缺、能源危机及环境污染等问题。不同植物底盘中也在逐步建成和完善标准化的元件体系、基因线路设计以及定向进化等合成生物学技术。本文回顾了近年来植物合成生物学的主要研究进展，详述了植物合成生物学在“双碳”目标中的应用领域，包含植物天然产物合成与次生代谢、分子农业、光合作用、碳汇植物的创制、植物工厂等。提出了植物基因文件标准化、植物基因线路设计、植物基因编辑和定向进化等助力“双碳”目标的植物合成生物学技术，并展望和探讨了在实现“双碳”目标过程中植物合成生物学的重要作用和发展前景。

关键词: 植物合成生物学, 碳达峰, 碳中和, 天然产物, 光合作用, 分子农业, 碳汇植物, 植物工厂