Photoactivatable enzyme upconverting lanthanide nanoparticle conjugates for low energy light driven biocatalysis

生物催化转化在当今经济中的重要性日益增加，这是推动更可持续技术和绿色化学合成的一部分。1利用太阳能实现光生物催化更具吸引力，最近在该领域取得了一些有影响力的创新。重要的是，光活化化学可以导致新的化学途径和新的化合物，迄今为止在热催化，开辟新的化学空间。在这方面，已经开发了具有UV或可见（蓝色）光的光-生物催化，其具有光氧化还原催化剂和光和/或使用非天然电子转移过程的活化酶以获得新的酶功能。在这里，我们提出了一种新的替代传统的高能紫外蓝光激活酶的方法，通过利用更多的太阳光谱和利用镧系上转换纳米颗粒（UCNP）2在酶-UCNP共轭物（转换近红外线（NIR）到紫外线或可见光），使光激活生物催化。在化学，生物学，分析化学和物理学的界面上，该项目将涉及制造一系列老黄酶家族的黄素酶和NADP（H）依赖性酶，这些酶共价连接到能够促进低能量光生物催化的UCNP。将对催化性能进行评估，并确定热活化催化和光活化催化（紫外可见光与近红外）在所产生产品方面的差异。激发态和瞬态自由基物种的性质将提供重要的机械信息，这些将由一套EPR技术与曼彻斯特的EPSRC国家EPR服务合作进行询问。此外，多组分和级联光生物催化的可能性将使用正交化学将不同的酶结合到相同的纳米颗粒上，例如3，以及原位生物结合策略的开发。

Biocatalytic transformations are gaining increasing importance in todays' economy as part of the drive towards more sustainable technology and green chemical synthesis.1 Harnessing solar energy to achieve photo-biocatalysis is even more attractive and several impactful innovations have recently been made in this field. Importantly, light activated chemistry can lead to new chemical pathways and new compounds hitherto unknown in thermal catalysis, opening up new chemical space. In this regard, photo-biocatalysis with UV or visible (blue) light has been developed with photoredox catalyts and light and/or activated enzymes using non-natural electron transfer processes to access new enzyme function. Here, we propose a new alternative to traditional high energy UV-blue light activated enzyme photocatalysis by exploiting more of the solar spectrum and taking advantage of lanthanide upconverting nanoparticles (UCNPs)2 in enzyme-UCNP conjugates (which convert near infra-red light (nIR) to UV or visible light) to enable light activated biocatalysis. At the interface of chemistry, biology, analytical chemistry and physics, this project will involve fabrication of a range of flavoenzymes of the old yellow enzyme family and NADP(H) dependent enzymes that are covalently tethered to UCNPs capable of promoting low energy photo-biocatalysis. Catalytic performance will be assessed and the difference between thermal and photo (UV-visible vs. nIR) activated catalysis in terms of the products produced established. The nature of the excited states and transient radical species will give important mechanistic information and these will be interrogated by a suite of EPR techniques in collaboration with the EPSRC National EPR service in Manchester. Additionally, the possibility of multicomponent and cascade photo-biocatalysis will be investigated using orthogonal chemistries to conjugate different enzymes to the same nanoparticle for example3 as well as the development of in situ bioconjugation strategies.