Raman Optical Activity Probing Structural Deformations of the 4-Hydroxycinnamyl Chromophore in Photoactive Yellow Protein.
Raman Optical Activity Probing Structural Deformations of the 4-Hydroxycinnamyl Chromophore in Photoactive Yellow Protein.
复制标题
DOI：
10.1021/jz400454j
复制
发表时间：
2013-04
期刊：
影响因子：
--
通讯作者：
Takahito Shingae;Kensuke Kubota;M. Kumauchi;F. Tokunaga;M. Unno
中科院分区：
文献类型：
--
作者：
Takahito Shingae;Kensuke Kubota;M. Kumauchi;F. Tokunaga;M. Unno
许多生物辅因子，例如光感受器中的光吸收发色团，含有π电子系统并且是平面分子。然而，这些辅因子在蛋白质环境中通常是非平面的，并且这种结构扭曲已被证明在功能上是重要的。由于非平面结构使分子手性，拉曼旋光（罗阿）提供了丰富的立体化学信息的结构和构象细节的辅因子。本研究应用近红外激发的罗阿光敏黄蛋白，蓝光受体。我们成功地获得了包埋在蛋白质环境中的4-羟基肉桂基发色团的罗阿光谱。此外，利用密度泛函理论计算的罗阿光谱提供了详细的结构信息，如数据的生色团的面外扭曲。从罗阿光谱获得的结构信息包括氢原子的位置，这通常在生物样品的晶体结构中检测不到。
Many biological cofactors, such as light-absorbing chromophores in photoreceptors, contain a π-electron system and are planar molecules. These cofactors are, however, usually nonplanar within a protein environment, and such structural distortions have been shown to be functionally important. Because the nonplanar structure makes the molecule chiral, Raman optical activity (ROA) provides a wealth of stereochemical information about the structural and conformational details of cofactors. The present study applied a near-infrared excited ROA to photoactive yellow protein, a blue light receptor. We successfully obtained the ROA spectra of the 4-hydroxycinnamyl chromophore embedded in a protein environment. Furthermore, calculations of the ROA spectra utilizing density functional theory provide detailed structural information, such as data on out-of-plane distortions of the chromophore. The structural information obtained from the ROA spectra includes the positions of hydrogen atoms, which are usually not detected in the crystal structures of biological samples.