Lukins P B, Oates T
School of Physics, A28, University of Sydney, Sydney, NSW 2006, Australia.
Biochim Biophys Acta. 1998 Nov 2;1409(1):1-11. doi: 10.1016/s0005-2728(98)00137-6.
Scanning tunneling microscopy (STM) and spectroscopy (STS) were used to obtain the first direct high resolution ( approximately 0.3 nm) images of single isolated Photosystem II (PS II) molecules, and to determine the supramolecular organization of oxygen-evolving PS II core complexes and PS II membrane fragments including the identification, assignment, location and dimensions of the polypeptide units. Our results predict a unique structural model which we then compare with alternative models. We show that the combination of quasi-constant-height mode STM operation, STS and suitable choice of sample-substrate preparations can be used to enable investigation of the structure and function of single PS II particles under normal thermodynamic and hydration conditions without the requirement and complications of ordered PS II arrays or crystals. STS was also used to characterize single-molecule electron conduction and tunneling mechanisms in PS II including the semiconduction and photoconduction behavior of the reaction center and photoexcitation effects in the light-harvesting complex LHC II.
扫描隧道显微镜（STM）和光谱学（STS）被用于获取单个分离的光系统II（PS II）分子的首批直接高分辨率（约0.3纳米）图像，并确定放氧PS II核心复合物和PS II膜片段的超分子组织，包括多肽单元的鉴定、归属、定位和尺寸。我们的结果预测了一个独特的结构模型，然后将其与其他模型进行比较。我们表明，准恒高模式STM操作、STS以及合适的样品-底物制备选择相结合，可用于在正常热力学和水合条件下研究单个PS II颗粒的结构和功能，而无需有序PS II阵列或晶体的要求和复杂性。STS还被用于表征PS II中的单分子电子传导和隧穿机制，包括反应中心的半导体传导和光电导行为以及光捕获复合物LHC II中的光激发效应。
