GAATTC is the recognization site for which of the following restriction endonuclease

Options

A. Hind III
B. EcoR I
C. Bam I
D. Hae III

Answer

To determine which restriction endonuclease recognizes the sequence GAATTC, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Restriction Endonucleases**:
- Restriction endonucleases, also known as restriction enzymes, are proteins that cut DNA at specific sequences. Each enzyme recognizes a unique sequence of nucleotides.

2. **Identify the Given Sequence**:
- The sequence provided in the question is GAATTC.

3. **Match the Sequence with Known Restriction Enzymes**:
- We need to identify which of the listed restriction endonucleases recognizes the sequence GAATTC. The options provided are:
- A. Hind III
- B. EcoRI
- C. BamHI
- D. HaeIII

4. **Recall the Recognition Sites of Each Enzyme**:
- Hind III recognizes the sequence AAGCTT.
- EcoRI recognizes the sequence GAATTC.
- BamHI recognizes the sequence GGATCC.
- HaeIII recognizes the sequence GGCC.

5. **Determine the Correct Answer**:
- From the above information, we can see that EcoRI is the restriction endonuclease that recognizes the sequence GAATTC.

### Final Answer:
- The restriction endonuclease that recognizes the sequence GAATTC is **B. EcoRI**.