Question

A cell biologist isolates a protein-RNA complex that exhibits catalytic activity. Treatment of this complex with RNase completely abolishes catalytic activity. However, treatment of the complex with proteases results in only a 15% decrease in catalytic activity. Which of the following is the most likely explanation for these data? 1) The catalytic activity of the complex is completely dependent on the protein component and only enhanced by the RNA component of the complex. 2) The catalytic activity of the complex is enhanced by the protein component and enhanced by the RNA component of the complex. 3) The catalytic activity of the complex is enhanced by the protein component and completely dependent on the RNA component of the complex. 4) The catalytic activity of the complex is independent of the protein component and only enhanced by the RNA component of the complex.

Answer 1

3

Step-by-step explanation:

RNases are enzymes that degrade RNA while proteases breakdown proteins.

This isolated protein-RNA complex has catalytic activity, meaning it is an enzyme that breaks down some molecules.

By treating this complex with Rnases and proteases and measuring the catalytic activity, the biologist can form an idea of the structure of the active site.

Rnase completely abolishes its activity. This means it is completely dependent on the RNA component since the protein structure is kept untouched.

The protease treatment only decreases the activity 15%, meaning even after altering its polypeptide structure, activity keeps high.

We can assume the most likely explanation for these data is option 3. The catalytic activity of the complex in enhanced by the protein component and completely dependent on the RNA component of the complex.