Spatio-temporal observation of structural changes in the optogenetic proteins halorhodopsin and YF1

光遗传学蛋白halorhodopsin和YF1结构变化的时空观察

• 批准号: 164462190
• 负责人: Professor Dr. Joachim Heberle
• 金额: --
• 依托单位: Institut für Experimentalphysik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/164462190?language=en
• 关键词: Spatio; temporal; observation; structural; changes

The goal of this project is the achievement of an atomic level understanding of the reaction mechanism of light switching in proteins. Reaching this objective requires a methodology with acute sensitivity and sufficient time-resolution. These requirements are met by vibrational spectroscopy. The structural changes are associated with vibrational changes of the chromophore, the protein backbone and amino acid side chains. Even minute alterations in hydrogen-bonding or protonation states are resolved by IR difference spectroscopy. We have developed surface-enhanced IR difference spectroscopy (SEIDAS) to apply this novel approach to monolayers of electron- as well as light-driven proteins. The methodology is able to monitor the impact of the electric field (or the membrane potential) on the functionality of the protein with atomis tic sensitivity (“voltage-clamp with infrared detection”). The IR data will be compared to surfaceenhanced resonance Raman spectroscopy (SERRS) which is selective for the vibrational modes of the chromophore, only. Primary target systems are the channelrhodopsins (ChR1 and ChR2 from Chlamydomonas reinhardtii and from Volvox carteri) which are light-gated ion channels. SEIDAS will provide molecular information on the gating mechanism which is regulated by the membrane potential. We are not only intensely collaborating with the groups that use electrophysiological techniques (Gottschalk, Hegemann, Nagel) but take advantage of the color tuning approaches developed by the Elstner & Hegemann group. We will continue our vibrational spectroscopic studies on the blue-light photoreceptors LOV and BLUF which will be expanded to include Aureochrome and PAC (in collaboration with the Hegemann, Nagel, Schlichting and Schwärzel groups).

该项目的目标是实现对蛋白质中光开关反应机制的原子水平理解。实现这一目标需要一种具有敏锐敏感性和足够时间分辨率的方法。振动光谱学满足这些要求。结构变化与发色团、蛋白质主链和氨基酸侧链的振动变化相关。即使是微小的氢键或质子化状态的变化，解决了红外差光谱。我们已经开发了表面增强红外差光谱（SEIDAS），将这种新的方法应用于单层的电子以及光驱动的蛋白质。该方法能够监测电场（或膜电位）对具有原子灵敏度的蛋白质的功能性的影响（“具有红外检测的电压钳”）。IR数据将与表面增强共振拉曼光谱（SERRS）进行比较，该光谱仅对发色团的振动模式具有选择性。主要靶系统是通道视紫红质（ChR1和ChR2来自莱茵衣藻和团藻），它们是光门控离子通道。SEIDAS将提供关于由膜电位调节的门控机制的分子信息。我们不仅与使用电生理技术的团队（Gottschalk，Hegemann，内格尔）密切合作，还利用Elstner和Hegemann团队开发的颜色调节方法。我们将继续对蓝光光感受器LOV和BLUF进行振动光谱研究，并将其扩展到包括Aureochrome和PAC（与Hegemann，内格尔，Schlichting和Schwärzel小组合作）。