Vibrational Changes Induced by Electron Transfer in Surface Bound Azurin Metalloprotein Studied by Tip-Enhanced Raman Spectroscopy and Scanning Tunneling Microscopy
Vibrational Changes Induced by Electron Transfer in Surface Bound Azurin Metalloprotein Studied by Tip-Enhanced Raman Spectroscopy and Scanning Tunneling Microscopy
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DOI：
10.1021/acsnano.7b07768
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发表时间：
2017-12-01
期刊：
影响因子：
17.1
通讯作者：
Zenobi, Renato
中科院分区：
文献类型：
--
作者：
Kradolfer, Stefan;Lipiec, Ewelina;Zenobi, Renato
铜蛋白天青蛋白由于其光学和振动特性与电子转移（ET）及其生物识别能力的特殊耦合，是生物电子、生物光电和生物传感器应用中非常有前途的候选者。然而，仍然缺乏对天青蛋白 ET 及其光学和电子振动特性与结合到导电表面的蛋白质中发生的电荷传输机制（生物传感器或生物电子元件的典型情况）相关的基本过程的完整理解。我们通过扫描隧道显微镜结合尖端增强拉曼光谱（STM-TERS）研究了与金电极表面结合的天青蛋白。获得了稳健的 TER 光谱，并且发现该蛋白质在光激发下与其配体-金属电荷转移带共振的振动响应受到隧道参数的影响，表明电子传输过程中活性位点振动的直接参与。
The copper protein azurin, due to the peculiar coupling of its optical and vibronic properties with electron transfer (ET) and its biorecognition capabilities, is a very promising candidate for bioelectronic, bio-optoelectronic and biosensor applications. However, a complete understanding of the fundamental processes relating azurin ET and its optical and vibronic characteristics with the charge transport mechanisms occurring in proteins bound to a conductive surface, the typical scenario for a biosensor or bioelectronic component, is still lacking. We studied azurin proteins bound to a gold electrode surface by scanning tunneling microscopy combined with tip-enhanced Raman spectroscopy (STM-TERS). Robust TER spectra were obtained, and the protein's vibronic response under optical excitation in resonance with its ligand-to-metal charge transfer band was found to be affected by the tunneling parameters, indicating a direct involvement of the active site vibrations in the electron transport process.