Q.
In the Avery, MacLoed, and McCarty experiment, which of the following enzyme did not affect the process of transformation?
2985
217
NTA AbhyasNTA Abhyas 2020Molecular Basis of Inheritance
Report Error
Solution:
Prior to the work of Oswald Avery, Colin MacLeod and Maclyn McCarty (1933-44), the genetic material was thought to be a protein. They worked to determine the biochemical nature of ‘transforming principle’ in Griffith's experiment. They purified biochemicals (proteins, DNA, RNA, etc.) from the heat-killed S-cells to see which ones could transform live R-cells into S-cells. They discovered that DNA alone from S-cells bacteria caused R bacteria to become transformed. They also discovered that protein-digesting enzymes (proteases) and RNA-digesting enzymes (RNases) did not affect transformation, so the transforming substance was not a protein or RNA. Digestion with DNase did inhibit transformation, suggesting that the DNA caused the transformation. They concluded that DNA is the hereditary material, but not all biologists were convinced.