Explain with the help of a suitable example the naming of a restriction endonuclease.

The naming of a restriction endonuclease is done in the following way:

• The first letter of the restriction endonuclease name comes from the genus and the second two letters come from the species of the prokaryotic cell from which they are isolated.

• For example: EcoRI comes from Escherichia coli RY 13. The letter ‘R’ in the name is derived from the name of the strain.

• Roman numbers following the name indicates the order in which the enzymes are isolated from the particular strain of bacteria.

(Endonucleases make cuts at specific positions within the DNA).