Recall what proteins are made of

Proteins are polymers of amino acids linked through peptide bonds.

Identify the type of amino acids present in proteins

In naturally occurring proteins, the amino acids are $\alpha$-amino acids. In these compounds, the amino group $(-NH_2)$ is attached to the $\alpha$-carbon, i.e. the carbon atom next to the carboxyl group $(-COOH)$.

General structure: $\mathrm{H_2N-CH(R)-COOH}$

What happens on hydrolysis of proteins?

Hydrolysis breaks peptide bonds and releases the constituent amino acids. Since proteins are made of $\alpha$-amino acids, hydrolysis gives $\alpha$-amino acids.

Evaluate the options

• A: $\gamma$ — Incorrect
• B: $\beta$ — Incorrect
• C: $\alpha$ — Correct
• D: $\delta$ — Incorrect

Final answer

The type of amino acids obtained by hydrolysis of proteins is: $\boxed{\alpha}$