Signal transduction in LOV and BLUF blue light photoreceptors.

本项目旨在获得含有黄素和视黄醛基光受体结构域的光激活酶的新结构信息。主要目标是了解传感光感受器域和调节输出实体之间的耦合，这是任何合理（重新）设计功能以增加潜在应用的先决条件。我们将重点关注Astasia和Beggiatoa的几种天然光激活环化酶（PAC）， Mougeotia的光激活激酶（phototropins）和Heterokontophytes的光调节转录因子（Aureochromes）的表达。此外，我们将研究定制设计的合成系统，其中光敏结构域诱导的结构变化揭示了与附加输出结构域的调节蛋白的相互作用区域。我们将通过一个通用的HAMP结构域连接器将经过充分研究的细菌环化酶与光敏的光紫红质（SRII）结合起来，从而设计出视紫红质环化酶嵌合体。所有具有功能和光活化的蛋白质都将进行结晶筛选以确定结构。结构表征的蛋白质将在体外和体内进行详细的酶学，光谱和功能研究。

This project aims at obtaining new structural information on light-activated enzymes containing flavin- and retinal-based photoreceptor domains. The major goal is to understand the coupling between the sensing photoreceptor domains and the regulated output entities, a prerequisite for any rational (re)design of function to increase potential applications. We will focus on the expression of several natural light-activated cyclases (PAC) of Astasia and Beggiatoa, light-activated kinases (phototropins) of Mougeotia, and light-regulated transcription factors (Aureochromes) of Heterokontophytes. In addition, we will work on custom-designed synthetic systems where the structural changes induced in the photosensor domain unmask interaction regions with regulatory proteins of the attached output domain. We will engineer rhodopsin-cyclase chimera by merging well-studied bacterial cyclases with the light-sensitive phoborhodopsin (SRII) via a versatile HAMP domain linker. All proteins that are functional and light-activatable will be subjected to crystallization screens for structure determination. Structurally characterized proteins will be studied in detail enzymatically, spectroscopically and functionally in vitro and in vivo.