Structure of orthorhombic crystals of beef liver catalase

The growth mechanisms and physical properties of the orthorhombic crystal form of beef liver catalase were investigated using in situ atomic force microscopy (AFM). It was observed that the crystals grow in the 〈001〉 direction by an unusual progression of sequential two-dimensional nuclei of half unit-cell layers corresponding to the `bottoms' and `tops' of unit cells. These were easily discriminated by their alternating asymmetric shapes and...