Identify the correct statements regarding EcoRI:

(A) It cuts DNA between A and T when GAATTC palindrome is present in the DNA
(B) It produces blunt ends in the fragments
(C) The blunt ends facilitates the action of the enzyme
(D) It cuts DNA between G and A when GAATTC sequence is present in the DNA
(E) GAATTC is the palindrome recognized by EcoRI

Choose the correct answer from the options given below :Only

(D) and (E) Only

The correct answer is Option (3) → (D) and (E) Only

Each restriction endonuclease functions by ‘inspecting’ the length of a DNA sequence. Once it finds its specific recognition sequence, it will bind to the DNA and cut each of the two strands of the double helix at specific points in their sugar -phosphate backbones. Each restriction endonuclease recognises a specific palindromic nucleotide sequences in the DNA.

For example, the following sequences read the same on the two strands in 5' → 3' direction. This is also true if read in the 3' → 5' direction.

5' —— GAATTC —— 3'

3' —— CTTAAG —— 5'

(D) It cuts DNA between G and A when GAATTC sequence is present in the DNA – EcoRI specifically cuts the DNA sequence between the G and A in the palindrome GAATTC, creating "sticky ends."

(E) GAATTC is the palindrome recognized by EcoRI – The sequence GAATTC is indeed the specific palindrome EcoRI recognizes and binds to.

The other options are incorrect:

• (A): EcoRI does not cut between A and T; it cuts between G and A in the sequence GAATTC.
• (B): EcoRI produces sticky ends, not blunt ends.
• (C): Sticky ends, not blunt ends, typically facilitate easier ligation for DNA fragments in genetic engineering.

So, the correct answer is (D) and (E) Only