Question

What are such sequences called? Name the enzyme used that recognises such nucleotide sequences.

Hint:

A DNA palindrome reads the same on both strands when the orientation (direction) of reading is kept the same.

Answer 1

Step 1: Understanding the Concept:
In molecular biology, certain DNA sequences read the same in both directions (5' to 3') on the two strands. These are targets for specific enzymes.
Step 2: Detailed Explanation:
The sequence provided is \( 5'-\text{GAATTC}-3' \) on the top strand and \( 3'-\text{CTTAAG}-5' \) on the bottom strand.
When read from \( 5' \rightarrow 3' \), both strands yield "GAATTC". This symmetry makes it a palindromic sequence.
Restriction Endonucleases are the "molecular scissors" that recognize these specific sequences and cut the DNA.
Specifically, the sequence \( 5'-\text{GAATTC}-3' \) is recognized by the enzyme EcoRI.
Step 3: Final Answer:
Type of sequence: Palindromic sequence.
Enzyme: Restriction Endonuclease (or specifically EcoRI).