The determination of catalase crystal structure by electron crystallography

The projected structure of beef liver catalase crystal has been determined by electron crystallography to a resolution of 0.7 nm. This crystal was prepared by glucose embedding technique to facilitate its preservation in vacuum and extremely low dose was also used to avoid irradiating damage. The information on which the projections are based was extracted from defocused low dose electron micrograph and electron diffraction pattern. Fourier analysis of the micrograph data provided the phase of the Fourier component of the structures. The electron diffraction pattern provided the amplitude.