Investigating The Effects Of Cyclisation On A Protein Tool And A Biocatalyst

植物和其他光合生物的光合作用非常高效，每年产生数十亿吨生物质。在这个物理化学过程中，阳光被空间和能量组织的天线捕获，光收集色素，如叶绿素。一旦被捕获，能量被转移到光系统I和II的反应中心，在那里它被转化并以化学键的形式储存起来。人们非常希望收集太阳能并生产设计的化学品和/或清洁燃料。从自然中获得灵感，这个博士项目旨在利用化学生物学和有机化学技术，将卷曲的蛋白质折纸（CCPO）笼子转化为未来应用的人工光合系统。在CCPO中，单个蛋白质链沿着欧拉轨迹折叠成三维形状，如多面体。多面体的侧面由螺旋（CC）二聚体片段组成，由两个以平行或反平行方向配对的α -螺旋组成。将CCPO笼转化为人工光合系统的第一步将涉及在蛋白质笼的边缘引入受体位点。这些受体位点将通过同步的动态共价反应，如二硫化物交换、硼酸盐和酰基肼的形成，用于天线的整合。与自然光合系统类似，这些合并的发色团将具有明确的距离和方向，以最大限度地提高可见光的吸收和转换效率。天线收集的可见光能量将被用于生产有价值的化学物质，通过合并反应中心进行催化。综上所述，将CCPO笼转化为可见光收集系统将是朝着开发高效的人工光合系统迈出的重要一步，该系统可以以清洁和有效的方式生产有价值的化学品。从长远来看，它推动了现有技术的发展，这些技术能够利用太阳能作为可再生能源的巨大潜力。

Photosynthesis by plants and other photosynthetic organisms is highly efficient contributing billions of tonnes of biomass every year. In this physiochemical process, sunlight is captured by spatially and energetically organised antennae, light harvesting pigments such as chlorophyll. Once captured the energy is transferred to reaction centres in photosystems I and II where it is converted and stored in the form of chemical bonds. It is greatly desired to harvest solar energy and produce designed chemicals and/or clean fuels. Taking inspiration from Nature, this PhD project aims to employ chemical biology and organic chemistry techniques to convert a coiled-coil protein origami (CCPO) cage into an artificial photosynthetic system for future applications. In CCPO, a single protein chain is folded along a Eulerian trail into a three-dimensional shape such as a polyhedron. The sides of the polyhedron are formed from coiled-coil (CC) dimer segments, composed of two alpha-helixes which are paired in either a parallel or antiparallel orientation. The first step in the conversion of a CCPO cage into an artificial photosynthetic system will involve the introduction of receptor sites onto the edges of the protein cage. These receptor sites will be employed for the incorporation of antennae through simultaneous dynamic covalent reactions such as disulphide exchange, boronate and acyl hydrazine formation. Similar to the natural photosynthetic system, these incorporated chromophores will have well-defined distances and orientations to allow maximum efficiency of visible light absorption and conversion. The visible light energy harvested by the antennae will be used for the production of valuable chemicals catalysed by the incorporation of a reaction centre. In summary, conversion of CCPO cages into visible light harvesting systems will be an important step towards the development of efficient artificial photosynthetic systems which can produce valuable chemicals in a clean and efficient manner. In the long run, it advances the technologies available that are capable of utilising the huge potential of solar energy as a renewable energy resource.