Question

The enzymes which are commonly used in genetic engineering are

• A. Endonuclease and ligase
• B. Restriction endonuclease and polymerase
• C. Ligase and polymerase
• D. Restriction endonuclease and ligase

Answer 1

Answer: (D)

A restriction enzyme or restriction endonuclease is an enzyme that cuts DNA at or near specific recognition nucleotide sequences known as restriction sites. Restriction enzymes are DNA-cutting enzymes found in bacteria (and harvested from them for use). Because they cut within the molecule, they are often called restriction endonucleases. Ligase is an enzyme that can catalyze the joining of two large molecules by forming a new chemical bond, usually with accompanying hydrolysis of a chemical group on one of the larger molecules or the enzyme.

Therefore, the correct answer is option D.