Question

You have created a recombinant DNA molecule by ligating a gene to a plasmid vector. By mistake, your classmate adds exonuclease enzyme to the tube containing the recombinant DNA. How will your experiment get affected as you plan to go for transformation now?

Answer 1

The experiment of transformation will likely not be affected by the addition of exonuclease enzyme to the recombinant DNA tube. This is because recombinant DNA molecules are circular and closed, lacking free ends. Exonuclease enzymes act by removing nucleotides from free ends of DNA molecules. Since the recombinant plasmid DNA is circular with no free ends, it will not be a substrate for exonuclease and thus will remain intact for transformation to proceed successfully.