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Bacteriophage P22, a member of the Podoviridae by morphology due to its short, non-contractile tail Bacteriophage T2, ... was the genetic material of life.
Hershey and Chase concluded that DNA, not protein, was the genetic material. They determined that a protective protein coat was formed around the bacteriophage, but that the internal DNA is what conferred its ability to produce progeny inside a bacterium. They showed that, in growth, protein has no function, while DNA has some function.
The genetic material of the bacteriophage, called a prophage, can be transmitted to daughter cells at each subsequent cell division, and later events (such as UV radiation or the presence of certain chemicals) can release it, causing proliferation of new phages via the lytic cycle. [1]
This genetic material uses the host cell's ribosomes to replicate, and synthesize proteins for the capsid and tail of the phage. New phages are assembled within the cell until the cellular membrane lyses (splits open).
In 1952, Hershey and Chase [19] provided key evidence that the phage DNA, as distinct from protein, enters the host bacterial cell upon infection and is thus the genetic material of the phage. This finding suggested that DNA is, in general, the genetic material of different organisms. [citation needed]
It happens when a phage is in the lytic stage, at the moment that the viral DNA is packaged into phage heads. If the virus replicates using 'headful packaging', it attempts to fill the head with genetic material. If the viral genome results in spare capacity, viral packaging mechanisms may incorporate bacterial genetic material into the new virion.
This experiment provided key evidence that DNA, as distinct from protein, is the genetic material of the phage and therefore the likely genetic material generally. In 1946, Luria made a finding that was destined to open up a new insight on how the stability of DNA is achieved (see Luria, [5] pg. 96).
Bacteriophage Lambda Structure at Atomic Resolution [1] Enterobacteria phage λ (lambda phage, coliphage λ, officially Escherichia virus Lambda) is a bacterial virus, or bacteriophage, that infects the bacterial species Escherichia coli (E. coli). It was discovered by Esther Lederberg in 1950. [2]