What is the source of EcoRI

Options

A. Escherichia coli RI
B. Escherichia coli RI 13
C. Escherichia coli RX 13
D. Escherichia coli RY 13

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the source of the restriction enzyme EcoRI.

2. **Identifying EcoRI**: EcoRI is a type II restriction endonuclease, which means it is an enzyme that cuts DNA at specific sequences.

3. **Source of EcoRI**: The source of EcoRI is a specific strain of bacteria. The options provided are various strains of *Escherichia coli*.

4. **Correct Strain Identification**: Among the options given:
- *Escherichia coli* Ri
- *Escherichia coli* Ri13
- *Escherichia coli* Rx13
- *Escherichia coli* Ry13

The correct source of EcoRI is *Escherichia coli* Ry13.

5. **Function of EcoRI**: EcoRI recognizes and cleaves a specific palindromic DNA sequence, which is 5' - GAA TTC - 3'. This recognition and cleavage are crucial in various biotechnology applications.

6. **Conclusion**: Therefore, the source of EcoRI is *Escherichia coli* Ry13.

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