Which of the following statement about the conformation (secondary and tertiary structure) of proteins is false ?

Options

A. The four atoms of an amide linkage `(-CO-NH-)` lie in a plane as a result of resonance between the nitrogen and the carbonyl group
B. Electrostatic attraction occurs between basic and acidic side chains
C. The favoured conformation of a protein is always that which has the greatest number of hydrogen bonds
D. The presence of the amino acid proline has the effect of turning a curner in a protein

Explanation

To determine which statement about the conformation (secondary and tertiary structure) of proteins is false, we will analyze each option provided.

### Step-by-Step Solution:

**Step 1: Analyze Option A**
- **Statement**: The four atoms of amide linkage (C=O, N-H) are in a plane as a result of resonance between nitrogen and carbon.
- **Analysis**: This statement is true. In an amide linkage, the resonance between the carbonyl (C=O) and the nitrogen (N-H) causes these atoms to adopt a planar configuration.

**Step 2: Analyze Option B**
- **Statement**: Electrostatic attraction occurs between basic and acidic side chains.
- **Analysis**: This statement is also true. Electrostatic interactions between positively charged (basic) and negatively charged (acidic) side chains contribute to the stability of the protein's tertiary structure.

**Step 3: Analyze Option C**
- **Statement**: The favorable conformation of the protein is always that which has the greatest number of hydrogen bonds.
- **Analysis**: This statement is false. While hydrogen bonds do contribute to the stability of protein structures, the overall conformation is influenced by various factors, including hydrophobic interactions, van der Waals forces, and steric hindrance. Therefore, a protein may adopt a conformation that is not solely based on maximizing hydrogen bonds.

**Step 4: Analyze Option D**
- **Statement**: The presence of the amino acid proline has the effect of turning a corner in protein structure.
- **Analysis**: This statement is true. Proline has a unique cyclic structure that introduces kinks or turns in the polypeptide chain, affecting the overall conformation of the protein.

### Conclusion:
The false statement about the conformation of proteins is **Option C**: "The favorable conformation of the protein is always that which has the greatest number of hydrogen bonds."