辅酶Q10作为线粒体呼吸链递氢体和天然抗氧化剂，对人体细胞能量供应和正常功能起着重要作用，在医药、保健和化妆品等领域有着广泛应用和巨大市场需求，目前大多通过微生物（主要为细菌）代谢工程生产。有着细菌共性的植物叶绿体不合成辅酶Q，但含有丰富的前体（IPP和分支酸）及其合成途径（MEP和莽草酸途径）。本课题拟通过叶绿体转化结合细胞核转化手段以及有效的多基因表达策略，人为向烟草叶绿体移植细菌辅酶Q10的合成途径，期望利用叶绿体固有的辅酶Q前体资源优势，异源从头并高水平地合成辅酶Q10，将叶绿体复原改造成富产辅酶Q10的光合细菌，从而建立一崭新且高效的植物代谢基因工程生产辅酶Q10的技术体系。另外，通过分析转基因植株的抗氧化胁迫能力和诸多逆境抗性以及叶绿体内源代谢物的含量变化，评判叶绿体合成辅酶Q10对植株的主要影响以及辅酶Q合成途径在叶绿体中的残存程度。总之，本课题具有显著的创新性和研究意义。

Coenzyme Q10, as the electron transmitter of the respiration chain and a native antioxidant in mitochondria, has important roles in energy supply and normal functions of human cells, being with broad applications and a huge market in the areas of medicine, healthcare, cosmetics and etc. Currently, it is mainly produced through the approaches of microbial (mostly as bacteria) metabolic engineering. Plant chloroplast, with many common features as bacterium, does not synthesize coenzyme Q, whereas it contains abundant related precursors (IPP and chorismate) and their corresponding biosynthetic pathways (MEP and Shikimate, respectively). In this project, we attempt to introduce artificially the pathway of bacterial coenzyme Q10 synthesis in tobacco chloroplasts by means of chloroplast transformation (or combined with nuclear transformation) and efficient strategies for multigene expression. De novo heterologous synthesis of high-level coenzyme Q10 in chloroplasts is to be expected, by making use of the large intrinsic availability of coenzyme Q precursors within chloroplasts. In this way, chloroplasts seem to be reverted to the photosynthetic bacteria rich in coenzyme Q10 production, and thus a new, efficient technique for producing coenzyme Q10 through plant metabolic genetic engineering is established. Moreover, the primary effects of synthesizing coenzyme Q10 in chloroplasts will be investigated by evaluating the performances of transgenic plants to resist the oxidative stress and other abiotic stresses as well as measuring the changes in the contents of endogenous target metabolites in chloroplasts. Meanwhile, the remnant degree of coenzyme Q biosynthesis pathway during chloroplast evolution will also get to be judged. Conclusively, this research is of considerable innovativeness and significance.