Who revealed biochemical nature of the transforming principle? How was it done?

1. When Griffith performed the experiment. He was unable to conclude the biochemical nature of the inherited genetic material.

2. After which Oswald Avery, Colin McLeod and Maclyn McCarty in 1933-34 performed an experiment to find this genetic material.

3. They purified the biochemicals (DNA, RNA, & Protein) from the heat killed S-strain cells.

4. They noticed that the RNA digesting enzyme (RNases) , Protein digesting enzymes (Proteases) did not affect the transformation of the non-virulent R-strain to the virulent S-strain.

5. This led to the conclusion that DNA was the transforming principle.