Restriction enzyme was discovered by

Options

A. Berger
B. Waksman
C. Flemming
D. Smith and Nathans

Answer

**Step-by-Step Solution:**

1. **Understand the Concept of Restriction Enzymes:**
- Restriction enzymes, also known as restriction endonucleases, are proteins that can cut DNA at specific sequences. They play a crucial role in molecular biology, particularly in genetic engineering and cloning.

2. **Analyze the Options Provided:**
- The question provides four options: Berger, Waksman, Fleming, and Smith and Nathans. We need to identify which of these individuals is credited with the discovery of restriction enzymes.

3. **Evaluate Each Option:**
- **Berger:** There is no significant contribution or discovery related to restriction enzymes attributed to a person named Berger.
- **Waksman:** He is known for discovering streptomycin and other antibiotics, but not restriction enzymes.
- **Fleming:** He discovered penicillin, the first antibiotic, but again, he is not associated with restriction enzymes.
- **Smith and Nathans:** They are recognized for their work on restriction enzymes and were awarded the Nobel Prize for their contributions to this field.

4. **Identify the Correct Answer:**
- Based on the evaluation, the correct answer is **Smith and Nathans**, as they are the scientists who discovered restriction enzymes.

5. **Conclude the Solution:**
- Therefore, the answer to the question "Restriction enzyme was discovered by" is **Smith and Nathans**.

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