By Team Aakash Byju's
Griffith injected mice with both S and R strains. While the one infected with the R strain survived, the one with the S strain got pneumonia and eventually died.
Frederick Griffith's Experiment
In their experiment, one set of viruses (A) was cultured in a radioactive phosphorus medium, whereas the second set (B) was cultured in a radioactive sulfur medium.
They discovered that the first group of viruses (A) had radioactive DNA but not radioactive proteins. The latter group of viruses (B) had radioactive protein but not radioactive DNA.
Provided experimental evidence for semiconservative DNA replication.
Meselson and Stahl's Experiment
For many generations on a medium containing 15NH4Cl. As a result, the nucleotide 15N was incorporated into the bacterial DNA.
Meselson and Stahl Cultivated E.coli