A restriction enzyme or restriction endonuclease is an enzyme that nicks or cuts DNA on a specific location after recognizing a specific sequence.
Restriction enzymes are widely used in cloning and biotechnological procedures.
The step of recombinant DNA technology requires the acquisition of the gene of interest (GOI). This is done by cutting it out of the donor genome.
Restriction enzymes perform this task by cutting on specific sequences. One important characteristic of restriction endonucleases is that they introduce "sticky ends" or overhangs in the donor sequence so it can be easily incorporated into the vector.
Lac operon (lactose) is degraded to glucose and galactose by three enzymes :beta galactosidase, galactoside permease and thiogalactosidase transacetylase.