Select the incorrectly matched pair from the following.
Explanation
Option D is the incorrectly matched pair. According to the context, 'The recognition sequences of widely applied Type II REs are palindromic sequences.' EcoRI recognizes a palindromic sequence (GAATTC) and cleaves DNA at specific locations within that sequence, which are characteristics of Type II restriction enzymes. Therefore, classifying EcoRI as a Type I Restriction Enzyme is incorrect. Options A, B, and C are correctly matched: Nucleases do hydrolyse phosphodiester bonds (as shown in Fig. 3.3), Restriction enzymes cleave DNA at specific sequences within the restriction sequence they recognize, and Palindromic sequences read the same in forward and reverse direction on the complementary strand.
Solution Steps
Step 1: Analyze Option A - Nucleases break phosphodiester bonds (Fig. 3.3 shows endonucleases break internal phosphodiester bonds). This is correctly matched.
Step 2: Analyze Option B - Restriction enzymes cleave DNA at specific sequences recognized by the enzyme. This is correctly matched.
Step 3: Analyze Option C - Palindromic sequences read the same in forward direction on one strand and reverse direction on the complementary strand. This is correctly matched.
Step 4: Analyze Option D - The context states that Type II REs have palindromic recognition sequences. EcoRI recognizes a palindromic sequence, making it a Type II enzyme, not Type I. This is incorrectly matched.