Metabolism USMLE Step 1 Practice Question
A biotechnology company engineers bacteria to produce human insulin by inserting a human gene into a plasmid vector. To generate compatible cohesive overhangs on both the plasmid and the gene of interest, researchers digest the DNA with bacterial enzymes that recognize specific palindromic sequences and create staggered cuts. PCR analysis confirms successful amplification of the target insulin gene sequence. No contaminating plasmid DNA remains after digestion. Which class of enzymes are the researchers using for this cloning procedure?
Answer choices
- ARestriction endonucleasesCorrect answer
- BTelomerases
- CDNA ligases
- DHelicases
- ETopoisomerases
- FSite-specific recombinases
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