Restriction endonuclease (REase)

Restriction endonucleases are enzymes, primarily found in bacteria and archaea, that recognize specific short DNA sequences and cleave double-stranded DNA at or near these sites[1][3][7]. Their natural function is to protect host cells from invading viral DNA by destroying unmethylated foreign sequences, while preventing damage to the host genome through co-expressed DNA methyltransferases. Restriction enzymes are highly diverse, structurally classified in types I–V according to nomenclature, mechanism, and sequence recognition features. In modern biotechnology, they are essential tools for genetic engineering, mapping of DNA, and various molecular biology applications[1][7].

Other names

Restriction enzymerestrictaseDNA sequence-specific endonuclease

Hydrolysis of phosphodiester bonds at specific DNA sequences, guided by recognition of a defined nucleotide motif[1][3][7]