After fractionation of mitochondrion‐free extracts of Xenopus laevis and Rana temporaria oocytes in sucrose gradients, a distinct peak of adenosine triphosphate (ATP)/guanosine triphosphate (GTP)‐binding activity in the 50–70 S range has been detected. This substance has a boyant density in Cs2SO4 of 1.45 g/cm3. The nucleotide‐binding substance has been purified to apparent homogenety. By means of electron microscopy, sodium dodecyl sulfate‐electrophoresis and other methods it has been identified as ferritin.
- Amphibian oocytes
- Ferritin Nucleotide‐binding