Departments of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel.
J Am Chem Soc. 2011 Mar 2;133(8):2421-3. doi: 10.1021/ja109989f. Epub 2011 Feb 4.
The temperature dependence of current-voltage values of electron transport through proteins integrated into a solid-state junction has been investigated. These measurements were performed from 80 up to 400 K [above the denaturation temperature of azurin (Az)] using Si/Az/Au junctions that we have described previously. The current across the ∼3.5 nm thick Az junction was temperature-independent over the complete range. In marked contrast, for both Zn-substituted and apo-Az (i.e., Cu-depleted Az), thermally activated behavior was observed. These striking temperature-dependence differences are ascribed to the pivotal function of the Cu ion as a redox center in the solid-state electron transport process. Thus, while Cu enabled temperature-independent electron transport, upon its removal the polypeptide was capable only of supporting thermally activated transport.
已经研究了通过集成在固态结中的蛋白质的电子传输的电流-电压值随温度的变化。这些测量是使用我们之前描述的 Si/Az/Au 结在 80 至 400 K [高于天青蛋白（Az）的变性温度]进行的。穿过厚度约为 3.5nm 的 Az 结的电流在整个范围内与温度无关。相比之下，对于 Zn 取代的和脱辅基的 Az（即 Cu 耗尽的 Az），都观察到了热激活行为。这些显著的温度依赖性差异归因于 Cu 离子作为固态电子传输过程中氧化还原中心的关键作用。因此，虽然 Cu 能够实现与温度无关的电子传输，但在 Cu 被去除后，多肽只能支持热激活的传输。
