Molecular Biology of the Gene 7th Edition by Richard Losick, James Watson, Michael Levine, Tamara Baker, Alexander Gann

Exercise 7

Audrey Stevens measured the incorporation of 32 P-labeled ADP or 32 P-labeled ATP into RNA. He added various nucleotides mixtures to an E. coli extract that catalyzed RNA synthesis. The added components per reaction are listed in the table below. The observed radioactivity incorporated into the RNA is listed in terms of cpm (counts per minute).

A. Based on your knowledge from this chapter and the data given, what enzyme do you think is present in the E. coli extract?
B. Why do you think the second reaction has the greatest cpm value compared to the other reactions?
Data adapted from Stevens (1960. Biochem. Biophys. Res. Commun. 3: 92-96).