Who confirmed protein nature of enzymes

Options

A. Monod et al
B. Arber et al
C. Berzelium
D. Northrop.

Answer

To answer the question "Who confirmed the protein nature of enzymes?", we can follow these steps:

### Step 1: Identify the Options
The options provided are:
1. Monod et al
2. Arbor et al
3. Barzilium
4. Nordrop

### Step 2: Recall Relevant Information
We need to recall which scientist or group of scientists is known for confirming that enzymes are proteins.

### Step 3: Analyze Each Option
- **Monod et al**: Known for work on allosteric regulation and enzyme kinetics but not specifically for confirming the protein nature of enzymes.
- **Arbor et al**: Not widely recognized for work related to enzymes.
- **Barzilium**: Not a recognized name in the context of enzyme studies.
- **Nordrop**: John Howard Nordrop is known for his work that confirmed the protein nature of enzymes.

### Step 4: Confirm the Correct Answer
Based on the information recalled, John Howard Nordrop confirmed the protein nature of enzymes. Therefore, the correct answer is option number four: Nordrop.

### Final Answer
The scientist who confirmed the protein nature of enzymes is John Howard Nordrop.

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