Virus particles molecular imaging

Point (b) is the more significant since many macromolecnlar assemblies do not have the fantastic symmetry of a virus particle or of GroEL or GroES. Therefore, the production of high resolution images becomes much more difficult where there is lower molecular symmetry, although far from impossible. 

FIGURE 1.12 Atomic force microscopy (AFM) also reveals the fundamental periodicity of macro-molecular crystals. In (a) is the surface layer of a crystal of brome mosaic virus, a particle having a diameter of about 280 A. In (b) is an AFM image of a monoclinic crystal of duodecahedral complexes of intact immunoglobulins, which have a diameter of about 230 A. 

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