Protein Structure and Denaturation

A researcher exposes a functional globular enzyme to a solution at 80°C and pH 2. After cooling and neutralizing the solution, the enzyme no longer catalyzes its reaction even though the amino acid sequence is unchanged.

1. (a) Identify the type of bond responsible for primary structure and describe how it forms between two amino acids. [2 points]

2. (b) Describe the interactions that stabilize secondary, tertiary, and quaternary structure. [3 points]

3. (c) Explain why exposure to 80°C and pH 2 inactivates the enzyme even though primary structure is preserved. [2 points]