An x-ray scattering study of ferritin and apoferritin.

摘要: Horse spleen ferritin has been fractionated according to density, and hence iron content, by equilibrium centrifugation in cesium chloride density-gradients. The separated fractions, including iron-free apoferritin, have studied solution small-angle X-ray scattering. scattering from apoferritin agrees well with that of a hollow sphere an outer radius 61 A inner 37 A. In order investigate the ferric hydroxide micelle independently protein coat which surrounds it, molecules were put 53% sucrose electron density matching (0·410 electrons/A 3 ). This essentially eliminates protein. “full ferritin”, molecule maximum was found molecular weight 418,000. curve for ferritin” agreed very uniform radius; it does not agree any spherical subunit structures reported many microscopists. As micelles decrease weight, they become more asymmetric so one dimension is always at least as large diameter center coat.