The first restriction endonuclease isolated was

Options

A. `EcoRl`
B. Bam-H
C. Sall
D. Hindll

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the first restriction endonuclease that was isolated. Restriction endonucleases are enzymes that cut DNA at specific sequences.

2. **Identifying the Options**: The options provided are:
- Eco R1
- BAM-H
- SOLVE
- HIN-D2

3. **Historical Context**: The first restriction endonuclease to be isolated was discovered in the early 1970s. It is important to recall the historical significance of these enzymes in molecular biology.

4. **Researching the Correct Answer**: The first restriction endonuclease that was isolated is known to be HindII, which is derived from the bacterium Haemophilus influenzae. This information is crucial for answering the question.

5. **Confirming the Function**: Restriction endonucleases, including HindII, recognize specific short sequences of DNA and cut them. They are naturally found in bacteria, which use these enzymes as a defense mechanism against invading viral DNA.

6. **Selecting the Correct Option**: Based on the historical context and the function of the enzyme, the correct answer to the question is HIN-D2.

**Final Answer**: The first restriction endonuclease isolated was HIN-D2.

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