Reaction: S-adenosyl-L-methionine + DNA adenine = S-adenosyl-L-homocysteine + DNA 6-methylaminopurine
Other name(s): modification methylase; restriction-modification system
Comments: This is a large group of enzymes, most of which, with enzymes of similar site specificity listed as EC 18.104.22.168 type 1 site-specific deoxyribonuclease, EC 22.214.171.124 type II site-specific deoxyribonuclease or EC 126.96.36.199 type III site-specific deoxyribonuclease, form so-called 'restriction-modification systems'. A complete listing of all of these enzymes has been produced by R.J. Roberts and is available on-line at http://rebase.neb.com/rebase/rebase.html.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 69553-52-2
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2. Roberts, R.J. Restriction enzymes and their isoschizomers. Nucleic Acids Res. 18 (1990) 2331-2365. [PMID: 2159140]
3. Yuan, R. Structure and mechanism of multifunctional restriction endonucleases. Annu. Rev. Biochem. 50 (1981) 285-319. [PMID: 6267988]