Question

What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium? I. Transform bacteria with a recombinant DNA molecule. II. Cut the plasmid DNA using restriction enzymes (endonucleases). III. Extract plasmid DNA from bacterial cells. IV. Hydrogen-bond the plasmid DNA to non-plasmid DNA fragments. V. Use ligase to seal plasmid DNA to non-plasmid DNA.

Answer 1

III. Extract plasmid DNA from bacterial cells

II. Cut the plasmid DNA using restriction enzymes (endonucleases)

IV. Hydrogen-bond the plasmid DNA to non-plasmid DNA fragments.

V. Use ligase to seal plasmid DNA to non-plasmid DNA.

I. Transform bacteria with a recombinant DNA molecule.

Step-by-step explanation:

In order to splice a foreign DNA into a plasmid and insert such plasmid into a bacterium, the following step-wise process has to be followed:

• The plasmid DNA from the bacterium cell is extracted.
• The plasmid which is circular in structure is then cut using restriction endonuclease.
• The plasmid DNA and the foreign DNA are then mixed together leading to the complementary ends attaching to each other by base pairing rule.
• The sticky ends of the DNAs are then sealed together by an enzyme known as ligase.
• The new, now recombined DNA is then introduced into the bacterium cell and the cell becomes transformed.

The correct order is III, II, IV, V, and I.