Mannella C A, Frank J
Ultramicroscopy. 1984;13(1-2):93-102. doi: 10.1016/0304-3991(84)90060-3.
Fourier-filtered images of negatively stained arrays of mitochondrial pore protein have been classified by correspondence analysis of their diffraction patterns. The most significant component of interpattern variation is an isotropic shift in reflection intensities between high- and low-order reflections. This corresponds in the images to the presence or absence of high resolution detail (stain minima). Experimentally the loss of detail in images correlates with the use of highly dissociated heavy metal salts as negative stains. It is proposed that such stains yield poorer negative-contrast images due to electrostatic binding of heavy-metal complex ions to fixed charge groups on the protein. Results with surface-modified protein arrays are consistent with this hypothesis.
通过对线粒体孔蛋白负染阵列的衍射图进行对应分析，对傅里叶滤波图像进行了分类。图案间变化的最显著成分是高阶和低阶反射之间反射强度的各向同性位移。这在图像中对应于高分辨率细节（染色最小值）的存在或不存在。实验表明，图像中细节的丢失与使用高度解离的重金属盐作为负染剂有关。有人提出，由于重金属络合离子与蛋白质上固定电荷基团的静电结合，这种染剂产生的负对比度图像较差。表面修饰蛋白质阵列的结果与这一假设一致。
