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Endonuclease
From Proteopedia
Template:STRUCTURE 1rva
Endonuclease (ENN) cleaves phosphodiester bond within polynucleotide chain. ENN cleaves DNA at a restriction site which is usually a 6-nucleotide palindrome. ENN is restriction site–specific. Various types of ENN differ by their mechanism of action. ENN is used in genetic engineering to make recombinant DNA. ENN requires a restriction site and a cleavage pattern. ENN-I operates on DNA with separate restriction site and cleavage pattern, while ENN-II operates on overlapping restriction site and cleavage pattern. Some ENNs are encoded within introns thus facilitating their mobility. These ENNs or inteins are designated I-ENN. The Cas ENN proteins are part of CRISPR/Cas prokaryotic immune system which confers protection from foreign genetic elements. The CRISPR (Custered Regularly Interspersed Short Palindromic Repeats) are DNA loci which are found in ca. 40% of the bacteria. For more details see Cas9. See also
3D structures of endonuclease
Updated on 23-December-2014
