关键词: 光合作用效率, 合成生物学, 光合电子传递模型, Rubisco改造, 光呼吸支路, 光合逆境适应

Abstract:

Photosynthesis is the primary source of energy and materials for nearly all life activities on Earth, and its efficiency directly impacts crop growth and yield. With the rapid development of synthetic biology, researchers have begun to explore engineering approaches to optimize the fundamental processes of photosynthesis at various levels, including light energy utilization, carbon fixation, photorespiration, and stress adaptation. This review summarizes recent advances in improving photosynthetic efficiency, with a focus on the synthetic biological strategies that can be implemented in crops. To achieve efficient light absorption and electron transport, novel light energy conversion models have been developed, involving the engineering of light-harvesting antennae to minimize energy loss and the development of orthogonal electron transport chains to enhance quantum yield. Multi-level optimization strategies have been developed for carbon assimilation pathways, including directed evolution and activity modification of Rubisco, optimization of key enzymes in the Calvin-Benson-Bassham cycle, and the introduction of CO₂ concentrating mechanisms into C₃ plants. Furthermore, novel photorespiratory bypasses have been engineered through synthetic biology approaches, which optimize glycolate metabolism to effectively reduce photorespiratory carbon loss while enhancing photosynthetic efficiency in crops. Additionally, various engineering strategies have been developed to optimize photosynthetic performance under adverse conditions, such as the enhancement of non-photochemical quenching components to tolerate high light and the application of stress-responsive elements to adapt to temperature fluctuations. By employing synthetic biology techniques, significant improvements in plant photosynthetic efficiency and stress resistance have been achieved. This has led to enhanced biomass and crop yields, thereby providing new solutions to address global food security challenges. In the future, strategies based on synthetic biology, combined with a deeper understanding of the molecular mechanisms of photosynthesis and emerging technologies like artificial intelligence, will offer more effective methods and pathways for the engineering of photosynthesis, resulting in a substantial enhancement of crop photosynthetic efficiency.

Key words: photosynthetic efficiency, synthetic biology, photosynthetic electron transfer model, Rubisco engineering, photorespiratory bypass, photosynthetic stress adaptation