Abstract：
In situ analysis of membrane protein-ligand interactions under physiological conditions is of significance for both fundamental and applied science, but it is still a big challenge due to the limits in sensitivity and selectivity. Here, we demonstrate the potential of surface-enhanced resonance Raman spectroscopy (SERRS) for the investigation of membrane protein-protein interactions. Lipid biolayers are successfully coated on silver nanoparticles through electrostatic interactions, and a highly sensitive and biomimetic membrane platform is obtained in vitro. Self-assembly and immobilization of the reduced cytochrome b5 on the coated membrane are achieved and protein native biological functions are preserved. Owing to resonance effect, the Raman fingerprint of the immobilized cytochrome b5 redox center is selectively enhanced, allowing for in situ and real-time monitoring of the electron transfer process between cytochrome b5 and their partners, cytochrome c and myoglobin. This study provides a sensitive analytical approach for membrane proteins and paves the way for in situ exploration of their structural basis and functions.
摘要：
生理条件下膜蛋白-配体相互作用的原位分析对基础科学和应用科学都具有重要意义。但由于灵敏度和选择性的限制，它仍然是一个巨大的挑战。这里,我们证明了表面增强共振拉曼光谱（SERRS）用于研究膜蛋白-蛋白相互作用的潜力。脂质生物层通过静电相互作用成功地涂覆在银纳米颗粒上，并在体外获得了高度敏感的仿生膜平台。实现了还原的细胞色素b5在包被膜上的自组装和固定，并保留了蛋白质的天然生物学功能。由于共振效应，固定化细胞色素b5氧化还原中心的拉曼指纹选择性增强，允许原位和实时监测细胞色素b5及其伙伴之间的电子转移过程，细胞色素c和肌红蛋白。本研究为膜蛋白提供了一种灵敏的分析方法，并为原位探索其结构基础和功能铺平了道路。
