Chemical and biological photoswitches

我们的目标是开发利用光控制蛋白质功能的一般方法。在这样做的过程中，我们制造了新的光开关分子，并学习如何将这些分子与蛋白质偶联以驱动功能转变。我们探索天然发光蛋白如何进化出新的功能，并开发体外进化和选择方法来生成化学生物学工具。 我们正在采取两种总体办法来实现这些目标。第一种是从发色团开始，从头设计光蛋白的“自下而上”方法。我们建议修改的生色团偶氮苯，它可以可逆地切换之间的反式和顺式状态的光，使其开关与近红外光。近红外可切换偶氮苯核心将使药物药理学，生物医学工程和药物输送的进步。我们的目标是找到一般的方法来连接偶氮苯为基础的开关蛋白质控制蛋白质折叠，从而发挥作用。我们将使用组合方法来找到基于偶氮苯的交联剂和交联位点，其允许fynomer的光控制，fynomer是小的抗体替代物。与此同时，我们将测试一种新的生物正交标记方法，靶向细胞内蛋白质，其中巯基为基础的交联是复杂的谷胱甘肽的存在。 我们的第二种方法从天然存在的光蛋白开始，探索这些蛋白如何工作，并试图将它们作为驱动其他蛋白质变化的元素。在天然光蛋白的再工程过程中，我们发现了光诱导的结构变化，包括结构域交换和β链滑移。这些光驱动的现象揭示了蛋白质动力学令人惊讶的基本特征。我们的目标是测试在β折叠中β链的复制通常是可以容忍的，以及这会导致新功能的频率。最后，我们将探索新的噬菌体展示技术来选择和进化发光蛋白。

We aim to develop general ways to control protein function using light. In so doing, we make new photoswitchable molecules and learn how to couple these to proteins to drive functional transitions. We explore how natural photo-proteins can evolve new function and we develop in vitro evolution and selection methods to generate tools for chemical biology. We are taking two general approaches to achieve these goals. The first is a 'bottom-up' approach starting with the chromophore and designing photo-proteins de novo. We propose to modify the chromophore azobenzene, which can be reversibly switched between trans and cis states by light, so that it switches with near-infrared light. A near-IR switchable azobenzene core would enable advances in photopharmacology, biomedical engineering and drug delivery. We aim to find general ways to attach azobenzene-based switches to proteins to control protein folding and thereby function. We will use a combinatorial approach to find azobenzene based cross-linkers and cross-linking sites that permit photo-control of fynomers, which are small antibody alternatives. In parallel, we will test a novel bio-orthogonal labelling approach for targeting intracellular proteins, where thiol-based cross-linking is complicated by the presence of glutathione. Our second approach starts with a naturally-occurring photo-proteins, explores how these work and tries to engineer them as elements for driving change in other proteins. In the process of re-engineering natural photo-proteins, we discovered remarkable light-induced structural transitions including domain swapping and beta-strand slippage. These light-driven phenomena reveal surprising fundamental features of protein dynamics. We aim to test where duplication of a beta strand is generally tolerated in beta-sheets and how often this can lead to new function. Finally, we will explore new phage display technologies to select and evolve photo-proteins.