The restriction enzyme BamHI recognises the sequence 5’-G^GATCC-3’, cleaving between the first and second G, as indicated. Which of the following restriction enzyme recognition sequences will be cleaved to give sticky ends that are compatible with those generated by BamHI?

Choose at least one answer.
a. 5’-C^GATCG-3’
b. 5’-^GATC-3’
c. 5’-TG^ATCA-3’
d. 5’-A^GATCT-3’
e. 5’-CTT^GATCAAG-3’

A,B,D,E

b. 5’-^GATC-3’

d. 5’-A^GATCT-3’
e. 5’-CTT^GATCAAG-3’

To determine which restriction enzyme recognition sequences will produce sticky ends compatible with BamHI, we need to analyze the sequence and identify the complementary sequence that will generate the same overhang.

The recognition sequence of BamHI is 5’-G^GATCC-3’. The caret (^) indicates the cleavage site. To find the complementary sequence, we need to determine the base pairing for each nucleotide.

In DNA, adenine (A) always pairs with thymine (T), and cytosine (C) always pairs with guanine (G). Therefore, the complementary sequence for BamHI is:

5’-G^GATCC-3’
3’-CCTAGG-5’

Now we will compare this complementary sequence with the given options and check which ones produce the same sticky ends:

a. 5’-C^GATCG-3’
This sequence has a mismatch at the third position (G instead of C). Therefore, it will not give sticky ends compatible with BamHI.

b. 5’-^GATC-3’
This sequence, although it lacks a preceding G, still has the same overhang as BamHI (5’-GATC-3’). Therefore, it will give sticky ends compatible with BamHI.

c. 5’-TG^ATCA-3’
This sequence has a mismatch at the second position (G instead of C). Therefore, it will not give sticky ends compatible with BamHI.

d. 5’-A^GATCT-3’
This sequence has a mismatch at the fifth position (C instead of G). Therefore, it will not give sticky ends compatible with BamHI.

e. 5’-CTT^GATCAAG-3’
This sequence has extra nucleotides before the recognition sequence. Therefore, it will not give sticky ends compatible with BamHI.

Therefore, the answer is option b. 5’-^GATC-3’. This sequence will cleave to give sticky ends that are compatible with those generated by BamHI.