Who Discovered Transformation?

Transformation: It is the genetic alteration of a cell resulting from the direct uptake and incorporation of exogenous genetic material from its surroundings and taken up through the cell membrane.

Principle:

1. The change in the DNA of an organism by picking up the DNA from the dead organism or environment is referred to as the transformation in Griffith's experiment.
2. The smooth (S) strain of Streptococcus pneumoniae is virulent and the rough (R) strain is non-virulent.
3. When the S strain was injected into the mouse it died but when the R strain was injected it lived.
4. When the heat-killed S strain alone was injected into the mouse it lived.
5. But when the R strain along with the heat-killed S strain was injected together the mouse died.
6. This is because the R strain has acquired some transforming principle from the heat-killed S strain and transformed into a virulent strain.

Discovered by:

1. Transformation was first demonstrated in 1928 by British bacteriologist Frederick Griffith.
2. In 1928, Frederick Griffith was credited with discovering transformation in Streptococcus pneumoniae.
3. Colin M, Oswald T. Avery, Maclyn McCarty, and MacLeod, 1944 exhibited that DNA was the transforming principle.