无细胞多酶分子机器赋能二氧化碳的高值利用及其挑战

Cell-freemulti-enzyme machines for CO_(2)capture,utilization and its associated challenges

二氧化碳等温室气体排放导致的全球气候变暖及相应的气候灾难日益严重,开发高效二氧化碳捕获和利用 技术迫在眉睫。利用生物制造技术固定二氧化碳是合成生物学工程科学的一个重要攻关方向,其中挖掘和组装无 细胞多酶分子机器赋能二氧化碳高值利用,由于背景清晰、调控相对简单、副反应少和产率高等优点,受到越来 越多的关注。近期,JamesC. Liao教授团队人工设计和开发了新型的多酶复合分子机器,建立了用于二氧化碳固 定的闭合循环反应-还原型乙醛酸-丙酮酸合成路径 (reductive glyoxylate-pyruvate synthesis cycle),可以理论上实现 2分子二氧化碳 (碳酸氢盐) 到 1分子乙醛酸的合成反应,并设计和尝试了反应过程中监控辅因子浓度以提高酶 稳定性的策略。本文基于设计和组装体外多酶分子机器,聚焦辅因子工程以及利用多酶分子机器固定二氧化碳所 面临的挑战等角度讨论这篇工作并简述作者的相关思考。

Global warming, mainly caused by the emission of carbon dioxide, is becoming a serious problem, and it is urgent to develop efficient carbon dioxide capture and utilization technologies. The use of biomanufacturing technology to fix carbon dioxide is an important research direction in synthetic biology. The mining and in vitro assembly of cell-free multi-enzyme machines have the great potential to facilitate the conversion of carbon dioxide into high-value products. The advantages associated with cell-free biosynthesis, such as clear background, relatively simple metabolic regulation, and high-yield production, make it ideal for biomanufacturing. Recently, the team of James C.Liao designed and developed a novel multi-enzyme molecular machine, and established a reductive glyoxylatepyruvate synthesis cycle, which can theoretically realize the conversion of 2 molecules of carbon dioxide(bicarbonate)to 1 molecule of glyoxylic acid. They also designed and developed a strategy to control the concentration of cofactors during the reaction to improve the enzyme stabilities. In this comment, we discuss this work from the perspectives of in vitro multi-enzyme assembly and cofactor engineering, and point to associated challenges of carbon dioxide utilization by multi-enzyme machines.