The paper by A. D. Hershey and Martha Chase investigates the independent functions of viral protein and nucleic acid in the growth of bacteriophage T2. They demonstrate that when phage T2 attaches to a bacterial cell, most of the phage DNA enters the cell, while a residue containing at least 80% of the sulfur-containing protein remains at the cell surface. This residue forms the protective membrane of the resting phage particle and plays no further role in infection after attachment. The authors find that little or none of the sulfur-containing protein is incorporated into the progeny phage, while phosphorus and adenine derived from the DNA are transferred to the phage progeny to a considerable extent. They conclude that sulfur-containing protein has no function in phage multiplication, and that DNA has some function. The study also shows that osmotic shock disrupts phage particles into material containing nearly all the phage sulfur and nearly all the phage DNA, with the sulfur-containing protein forming a protective membrane. Additionally, adsorption of T2 to heat-killed bacteria or heating/alternate freezing-thawing of infected cells sensitizes the DNA of the adsorbed phage to DNase, suggesting that the DNA forms part of an organized intracellular structure during phage growth.The paper by A. D. Hershey and Martha Chase investigates the independent functions of viral protein and nucleic acid in the growth of bacteriophage T2. They demonstrate that when phage T2 attaches to a bacterial cell, most of the phage DNA enters the cell, while a residue containing at least 80% of the sulfur-containing protein remains at the cell surface. This residue forms the protective membrane of the resting phage particle and plays no further role in infection after attachment. The authors find that little or none of the sulfur-containing protein is incorporated into the progeny phage, while phosphorus and adenine derived from the DNA are transferred to the phage progeny to a considerable extent. They conclude that sulfur-containing protein has no function in phage multiplication, and that DNA has some function. The study also shows that osmotic shock disrupts phage particles into material containing nearly all the phage sulfur and nearly all the phage DNA, with the sulfur-containing protein forming a protective membrane. Additionally, adsorption of T2 to heat-killed bacteria or heating/alternate freezing-thawing of infected cells sensitizes the DNA of the adsorbed phage to DNase, suggesting that the DNA forms part of an organized intracellular structure during phage growth.