ECoRI is obtained from…

Options

A. Escherichia coli R13
B. Escherichia coli Ry13
C. Escherichia coli R225
D. Escherichia coli RC

Answer

**Step-by-Step Solution:**

1. **Understanding ECoRI**: ECoRI is a restriction endonuclease enzyme. Restriction endonucleases are enzymes that can cut DNA at specific sequences, which is crucial for molecular biology applications.

2. **Identifying the Source**: ECoRI is derived from a specific strain of bacteria. In this case, it is obtained from Escherichia coli, which is a common bacterium found in the intestines of warm-blooded organisms.

3. **Specific Strain**: The specific strain of Escherichia coli from which ECoRI is obtained is known as RY13. This strain produces the ECoRI enzyme that recognizes and cuts DNA at a specific sequence.

4. **Recognition Sequence**: The recognition sequence for ECoRI is GAA TTC. This means that ECoRI will cut the DNA at this specific sequence, separating the strands at that point.

5. **Conclusion**: Therefore, ECoRI is obtained from Escherichia coli RY13.

**Final Answer**: ECoRI is obtained from Escherichia coli RY13.

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