1.  Osmotic Shock disrupts particles of phage T2 into material containing nearly
         all phage sulfur in a form precipitable by antiphage serum, and capable of
         specific adsorption to bacteria. Releases into solution nearly all the phage
         DNA in a form not precipitable by antiserum and not adsorbable to
         bacteria.The sulfur-containing protein of the phage particle makes up a
         membrane
            i)     Protecting DNA from DNase
            ii)    comprises principle antigenic material
            iii)    attachment of phage to bacteria.

    2.  Adsorption of T2 to heat-killed bacteria, and heating or alternate freezing of
         infected cells, sensitizes DNA of adsorbed phage to DNase.

        Unadsorbed phage not sensitized by these treatments.

        Heating or freezing and thawing does not release the phage DNA from
        infected cells, but other cell constituents can be extracted by these methods.

         Suggests phage DNA forms part of an organized intracellular structure
         throughout the period of phage growth.

    3.  Adsorption of phage T2 to bacterial debris causes part of the phage DNA to
         appear in solution leaving phage sulfur attached to debris.

    4.  Suspensions of infected cells agitated in a Waring blender released 75% of
         phage sulfur and only 15% of phage phosphorus to solution as a result of
         applied shearing force.

         Cells remain capable of yielding phage progeny.

    5.   Facts show most of phage sulfur remains at cell surface and most of
          phage DNA enters the cell on infection.

    6.    Phage progeny yielded by bacteria infected with S35 labeled phage are not
           labeled themselves.  (>1%).
 

   "The sulfur containing protein of resting phage particles is confined to a protective coat that is responsible for the adsorption to bacteria, and functions as an instrument for the injection of the phage DNA into the cell. This protein probably has no function in the growth of intracellular phage.

THE DNA PROBABLY HAS SOME FUNCTION ..."

                                                                             - A.D. Hershey & Martha Chase
 

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