Where is the pump switch of bacteriorhodopsin located?

细菌视紫红质的泵开关位于哪里？

• 批准号: 14380316
• 负责人: KANDORI Hideki
• 金额: $ 9.6万
• 依托单位: Nagoya Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14380316/
• 关键词: bacteriorhodopsin; FTIR; proton pump; hydrogen bond; internal water molecule; light sensor; vectorial transport; isotope effect; 能動輸送; エントロピー減少; 光異性化反応; 水素結合ネットワーク; 内部結合水

This research project aims at revealing the mechanism of proton pump in bacteriorhodopsin(BR). For this aim, we applied low-temperature polarized Fourier-transform infrared(FTIR) spectroscopy. Highly accurate FTIR spectroscopy of BR and related proteins provided the following results.(1)A new model for the primary proton transfer reaction is proposed based on the detailed structural analysis of internal water molecules in BR by low-temperature FTIR spectroscopy. This method led to the so called "hydration switch model". According to the model, the proton transfer reaction is controlled by a hydration switch of a water molecule from Asp85 to Asp212.(2)By use of isotope label and mutant proteins, we identified stretching vibrations of the protonated Schiff base and Arg82,both of which constitute hydrogen-bonding network in BR.(3)Hydrogen-bonding network in halorhodopsin, a light-driven chloride ion pump, is studied. We found that a chloride ion is hydrated by internal water molecules differently from those in BR.(4)Complex formation between pharaonis phoborhodopsin and its transducer protein was detected by FTIR spectroscopy.(5)Protein structural changes of Neurospora rhodopsin and visual rhodopsin were studied. Unique hydrogen-bonding structures are revealed.

本研究旨在揭示细菌视紫红质（BR）中质子泵的作用机制。为此，我们采用低温偏振傅里叶变换红外（FTIR）光谱。BR和相关蛋白质的高精度FTIR光谱提供了以下结果。(1)A基于低温FTIR光谱对BR内部水分子结构的详细分析，提出了一种新的初级质子转移反应模型。这种方法导致了所谓的“水合开关模型”。根据该模型，质子转移反应是由水分子从Asp85到Asp212的水合开关控制的。(2)By利用同位素标记和突变蛋白，我们确定了质子化Schiff碱和Arg82的伸缩振动，它们都构成了BR中的氢键网络。（3）研究了光驱动氯离子泵盐视紫红质中的氢键网络。我们发现，氯离子是水合的内部水分子不同于那些在BR。（4）FTIR光谱检测到法老视紫红质与其转导蛋白之间形成复合物。（5）研究了脉孢菌视紫红质和视紫红质的蛋白质结构变化。揭示了独特的氢键结构。

项目成果

Water Structural Changes in the Activation Process of the LOV2 Domain of Adiantum Phytochrome3.

铁线蕨光敏色素 3 的 LOV2 结构域激活过程中水结构的变化。

• 发表时间: 2005
• 期刊: J.Mol.Struct. 735/736
• 作者: Lorenz Fonfria;Kandori;Mune da et al.;Furutani et al.;Shibata et al.;Mizuide et al.;Zikihara et al.;神取秀樹;Nozaki et al.
• 通讯作者: Nozaki et al.

Role of Asp193 in Chromophore-Protein Interaction of pharaonis Phoborhodopsin (Sensory Rhodopsin II)

Asp193 在法老紫红质（感觉视紫红质 II）发色团-蛋白质相互作用中的作用

• 发表时间: 2002
• 期刊: Biophys.J. 83
• 作者: M.Iwamoto et al.

T.Iwata et al.: "Light-induced structural changes in the LOV2 domain of Adiantum phytochrome3 studied by low-temperature FTIR and UV-visible spectroscopy"Biochemistry. 42. 8183-8191 (2003)

T.Iwata 等人：“通过低温 FTIR 和紫外-可见光谱研究铁线蕨光敏色素 3 的 LOV2 结构域的光诱导结构变化”生物化学。

神取秀樹: "光駆動プロトンポンプの方向性を決める反応"化学. 57. 58-59 (2002)

Hideki Kandori：“决定光驱动质子泵方向性的反应”化学 57. 58-59 (2002)。

FTIR Spectroscopy of the O Photointermediate in pharaonis Phoborhodopsin

法老紫磷紫红质中 O2 光中间体的 FTIR 光谱

• 发表时间: 2004
• 期刊: Biochemistry (発表予定)
• 作者: Y.Furutani et al.