Question

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

Answer 1

The biochemical nature of the transforming principle:

The biochemical nature of the transforming principle was revealed by Oswald Avery, Colin Macleod and Maclyn McCarty.

• They purified the biochemicals from the heat killed S-strain i.e. protein, DNA and RNA and injected it into the mice along with the R strain.
• The transformation happened only when DNA was used.
• They also found that presence of protease and RNase does not have any effect on the transformation, but presence of DNase inhibited the transformation.
• Thus they concluded that DNA is the hereditary material.