Question

Consider an experiment where you digest a DNA molecule with restriction enzyme BclI. You resolve the products of the digest by gel electrophoresis. Then, you cut out each of the resulting two bands from the gel and sequence the DNA. The sequencing results return two DNA segments.
Segment 1
5′ CCGCGGT 3′
3′ GGCGCCACTAG 5′
Segment 2
5′ GATCAGGATCC 3′
3′ TCCTAGG 5′
1. What is the sequence of the BclI recognition site?
2. What type of ends do the products have?

Answer 1

Answer:

This BclI restriction enzyme recognizes and cut at T / CTAG nucleotide sequences.

Explanation:

5′ CCGCGGT 3′

3′ GGCGCCACTAG 5′

Segment 2

5′ GATCAGGATCC 3′

3′            TCCTAGG 5′

The BclI enzyme generates sticky ends, it means that the enzyme recognises and cuts nucleotide sequences without complementary bases, which also have weak hydrogen bonds. The sticky ends are then generated when an enzyme produces unpaired nucleotide ends. Nonetheless, restriction enzymes generally produce blunt ends, i.e., both strands cut at the same site.