Direct electrochemistry of thermophilic cytochrome P450

细胞色素p450用还原性活化的分子氧催化惰性烃分子的选择性氧化。细胞色素p450在生物传感器和生物反应器等生物器件中具有潜在的应用价值。对细胞色素P450催化反应进行电化学控制，由于系统的促进作用，使其应用范围扩大。研究了PEO修饰的P450st在PEO200溶剂中的直接电子转移。我们还通过紫外-可见吸收，共振拉曼光谱和电化学方法研究了嗜热细胞色素p450 -二十二烷基二甲基溴化铵（DDAB）薄膜的表征。拉曼光谱显示，DDAB薄膜在玻璃载玻片表面呈现近似天然的构象，而在PFC电极表面，P450st-DDAB的构象与DDAB薄膜的构象非常相似，说明PFC电极上DDAB薄膜中的P450st释放了血红素。当NaBr作为盐加入到铸膜溶液中时，拉曼光谱结果显示P450st在DDAB薄膜中甚至在PFC电极上也具有接近天然结构，但没有观察到具有接近天然结构的P450st的氧化还原电位。这项研究表明，当使用血红素蛋白- ddab薄膜时，必要的实验条件，因为在某些情况下，蛋白质中的血红素铁被释放到电极表面。

Cytochrome P450s catalyze the selective oxidation of inert hydrocarbon molecules with reductively activate molecular oxygen. Cytochrome P450s have a potentially useful application for biodevices such as biosensors and bioreactors. Electrochemical controlling of the cytochrome P450 catalytic reaction will cause the application to spread because of system facilitation. We investigated the direct electron transfer of P450st modified with PEO in PEO200 solvent at remarkably high temperatures.We have also studied the characterization of thermophilic cytochrome P450-didodecyldimethylammoniumbromide (DDAB) films by using UV-vis absorption, resonance Raman spectroscopy, and electrochemical methods. The observed Raman spectrum indicated near-native conformation of the heme iron in DDAB film on the surface of a glass slide, while on the surface of a plastic-formed carbon (PFC) electrode, the conformation of P450st-DDAB was very similar to that of heme-DDAB film, suggesting the release of heme from P450st in DDAB films on PFC electrodes. When NaBr was added as salt to the casting solution, the result of Raman spectrum indicated near-native conformation of P450st in DDAB film even on the PFC electrode, but no redox potential of P450st which has near native structure was observed. This study suggests the essential experimental conditions when working with heme protein-DDAB films as, in some cases, heme iron from proteins is released on the surface of the electrode.