Silicon content of intact nuclear polyhedra from the corn earworm, Heliothis zea

Analysis of intact and whole inclusion bodies of the corn earworm, Heliothis zea, showed a silicon content of 0.12 percent of the weight of the total body. The presence of silicon in the polyhedral protein and the absence of this element in the virus rod were demonstrated. However, the possibility remained that under the in vitro conditions of virus liberation, the silicon might have been present in the virus but was lost prior to assay. Evidence gathered supported the idea that dissolution of the polyhedral protein material was primarily attendant upon solubilization of the silicates protein material was primarily attendant upon solubilization of the silicates present. A framework or skeletal function was thus assigned to these silicates. A possible function for magnesium and iron ions present in the polyhedra is discussed in the light of their possible incorporation into the silicate lattice.