Table of Contents
What enzyme do scientists use to bond a new gene to plasmid DNA?
DNA ligase
DNA ligase is a DNA-joining enzyme. If two pieces of DNA have matching ends, ligase can link them to form a single, unbroken molecule of DNA. In DNA cloning, restriction enzymes and DNA ligase are used to insert genes and other pieces of DNA into plasmids.
How do we put new genes into a plasmid?
The basic steps are:
- Cut open the plasmid and “paste” in the gene. This process relies on restriction enzymes (which cut DNA) and DNA ligase (which joins DNA).
- Insert the plasmid into bacteria.
- Grow up lots of plasmid-carrying bacteria and use them as “factories” to make the protein.
What enzyme is used to rejoin the DNA?
Restriction enzymes, found naturally in bacteria, can be used to cut DNA fragments at specific sequences, while another enzyme, DNA ligase, can attach or rejoin DNA fragments with complementary ends.
What enzyme cuts plasmids prior to gene insertion?
Restriction enzymes
Restriction enzymes cut DNA at specific 4- to 8-bp sequences, often leaving self-complementary single-stranded tails (sticky ends). These enzymes are used to cut long DNA molecules into multiple restriction fragments and to cut a plasmid vector at a single site.
What enzyme synthesizes the new DNA strand?
DNA polymerase
The enzyme that synthesizes DNA, DNA polymerase, can only add nucleotides to an already existing strand or primer of DNA or RNA that is base paired with the template. An enzyme, DNA polymerase, is required for the covalent joining of the incoming nucleotide to the primer.
How do you find the restriction enzyme site in a sequence?
Search for enzymes by name or number of cut sites Open a DNA sequence. Then, open the Digests panel by clicking the scissors icon on the right nav bar. The search box that opens allows searching for enzymes by name or number of cuts.