Abstract
The paracrystalline structures appearing in human adenovirus-infected KB and human embryonic lung fibroblast cells have been shown by immunofluorescent-staining procedures to be serologicaly related to the adenovirus core protein(s) the arginon and P-antigen components described by others. Cytochemical staining and arginine-depletion studies demonstrated the arginine-rich nature of the paracrystalline formations. It was possible, using proflavine or decreased amounts of arginine in the culture medium, to block the assembly of intact virus particles without affecting the appearance of the paracrystals.