Question

EcoRI recognizes the sequence 5'-G|AATTC-3' ("|" indicates the point of cleavage). Treatment of the following oligonucleotide with EcoRI would produce two oligonucleotides with sizes of _____ double-stranded nucleotides containing _____ ends. 5'-AAGTCGATACAGAATTCGTACCTAG-3'

a) 10, 5'-AAGT
b) 12, 5'-AAGTCGATACA
c) 14, 5'-AAGTCGATACAGA
d) 16, 5'-AAGTCGATACAGAA

Answer 1

EcoRI cleaves the provided oligonucleotide to produce two fragments. The shorter oligonucleotide is 10 nucleotides long with 5'-AAGT as the sticky end. The correct option is A.

Step-by-step explanation:

When the oligonucleotide 5'-AAGTCGATACAGAATTCGTACCTAG-3' is treated with EcoRI, which recognizes the sequence 5'-G|AATTC-3', it will cleave the DNA at the sequence GAATTC.

The cleavage site within the provided oligonucleotide is directly before the G in AAGTCGATACAGAATTCGTACCTAG, producing two DNA fragments with cohesive or sticky ends.

Based on the cleavage points, two oligonucleotides will be produced: a shorter one with the sequence 5'-AAGT and a longer one with the remaining nucleotides. Therefore, the correct answer is:

a) 10 double-stranded nucleotides containing 5'-AAGT ends