Who first reported of restriction enzyme in bacterial cells?

Options

A. Arber
B. Laderberg
C. Smith
D. Sanger

Answer

**Step-by-Step Solution:**

1. **Understanding Restriction Enzymes**:
- Restriction enzymes are specific enzymes that cut DNA at or near specific nucleotide sequences. They are crucial in biotechnology for DNA manipulation.

2. **Historical Context**:
- The discovery of restriction enzymes dates back to the 1960s. During this period, researchers were investigating the interactions between bacteriophages (viruses that infect bacteria) and bacterial cells.

3. **Key Scientists Involved**:
- The first report of restriction enzymes came from two scientists, Arbor and Stewart. They were studying the behavior of bacteriophages when they infected resistant strains of bacteria.

4. **Observation Made**:
- Arbor and Stewart observed that when bacteriophages invaded resistant bacterial strains, the bacteriophage DNA was degraded and cut into smaller pieces. This led them to conclude that there were enzymes present in the bacteria that were responsible for this degradation.

5. **Identification of the Source**:
- The specific bacteria they studied was E. coli. They identified that the restriction enzymes responsible for cutting the bacteriophage DNA were derived from E. coli.

6. **Conclusion**:
- Based on their findings, Arbor and Stewart are credited with the first report of restriction enzymes in bacterial cells. Therefore, the correct answer to the question is Arbor.

**Final Answer**: Arbor

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