Restriction digest

Restriction enzymes can be used as molecular scissors that specifically cut DNA sequences. The optimal activity of each restriction enzyme is affected by conditions such as temperature, pH, enzyme cofactor, salt composition, and ionic strength.

Restriction digests are used for:

  • Molecular cloning, to clone DNA fragments into a plasmid.

  • Restriction mapping takes advantage of the sequence specificity of restriction enzymes. If the sequence of a DNA fragment is known, a restriction digest and gel electrophoresis can be used to identify specific sequences, like a molecular fingerprint.

  • Digestion of whole genomes for Southern blot analysis.