a) BamHI, cleaves after the first G:
3’ GGATCC 5’
5’ CCTAGG 3’
Does cleavage by BamHI result in a 5’ or 3’ overhang? What is the sequence of this overhang? [1]
To determine whether cleavage by BamHI results in a 5' or 3' overhang, we need to analyze the sequence of the enzyme's recognition site.
BamHI recognizes the sequence 5' GGATCC 3' and cleaves after the first G in the sequence.
Since the cleavage site is after the first G (highlighted in bold), the cut site can be represented as follows:
3’ G--GATCC 5’
This indicates that the overhang is on the 5' end.
The sequence of the overhang is G. Thus, the 5' overhang sequence for BamHI is G.
So, to summarize, cleavage by BamHI results in a 5' overhang with a sequence of G.