Do eukaryotic cells have restriction endonucleases? Justify your answer.

No, eukaryotic cells do not have restriction endonucleases. All restriction endonucleases have been isolated from various strains of bacterias till date. Even the restriction endonucleases are named according to the genus, species, strains and isolation number of the bacterias. The first letter of the restriction endonuclease is the genus and the last two is the species of the organism. The subscript is first letter the strain of the organism, if already used the next letter is used. The Roman numbers in the end is the isolation number of the enzyme chronologically when the organism has more than one restriction endonuclease.

Example: EcoRI, where “E” is for the genus of organism Escherichia. “co” is for coli, which is the species. “R” belongs to the strain of E. coli from which EcoRI is isolated, that is, RY13. And the Roman numeral “I” says it is the first isolated endonuclease of the organism E. coli (RY13).