From the following, the statement /s that will help to determine the specificity of an enzyme is /are:
I. The bonding between R groups of amino acids of the polypeptide
II. The optimum pH of the enzyme
III. The peptide bonds between amino acids of the polypeptide
IV. The shape of the substrate molecule

Options

A. I,II,III and IV
B. I and III only
C. I only
D. II,III and IV only

Answer

To determine the specificity of an enzyme, we need to analyze each statement provided in the question.

1. **Statement I: The bonding between R groups of amino acids of the polypeptide.**
- This statement is correct. The specific interactions (such as hydrogen bonds, ionic bonds, hydrophobic interactions, etc.) between the R groups of amino acids in the enzyme's structure contribute significantly to the enzyme's active site configuration. This configuration is crucial for the enzyme's ability to bind to its specific substrate.

2. **Statement II: The optimum pH of the enzyme.**
- This statement is incorrect in the context of determining specificity. While the optimum pH is important for enzyme activity, it does not directly determine the specificity of the enzyme. Specificity is more related to the structure of the enzyme and its active site rather than the pH at which it functions best.

3. **Statement III: The peptide bonds between amino acids of the polypeptide.**
- This statement is also incorrect. Peptide bonds link amino acids together to form the polypeptide chain, but they do not influence the specificity of the enzyme. Specificity is determined by the arrangement and interactions of the R groups rather than the peptide bonds themselves.

4. **Statement IV: The shape of the substrate molecule.**
- This statement is incorrect in the context of determining the specificity of the enzyme. While the shape of the substrate is important for the enzyme-substrate interaction, it is the enzyme's active site shape that is crucial for specificity. The specificity is determined by how well the enzyme's active site complements the shape of the substrate.

### Conclusion:
From the analysis, the only statement that helps to determine the specificity of an enzyme is **Statement I**. Therefore, the correct answer is **Option 3: 1 only**.