IUBMB Enzyme Nomenclature


Accepted name: type I site-specific deoxyribonuclease

Reaction: Endonucleolytic cleavage of DNA to give random double-stranded fragments with terminal 5'-phosphates; ATP is simultaneously hydrolysed

Other name(s): type I restriction enzyme; deoxyribonuclease (ATP- and S-adenosyl-L-methionine-dependent); restriction-modification system; deoxyribonuclease (adenosine triphosphate-hydrolyzing); adenosine triphosphate-dependent deoxyribonuclease; ATP-dependent DNase; type 1 site-specific deoxyribonuclease

Comments: This is a large group of enzymes which, together with those now listed as EC (type II site-specific deoxyribonuclease) and EC (type III site-specific deoxyribonuclease), were previously listed separately in sub-subclasses EC 3.1.23 and EC 3.1.24. They have an absolute requirement for ATP (or dATP) and S-adenosyl-L-methionine. They recognize specific short DNA sequences and cleave at sites remote from the recognition sequence. They are multifunctional proteins that also catalyse the reactions of EC [site-specific DNA-methyltransferase (adenine-specific)] and EC [DNA (cytosine-5-)-methyltransferase], with similar site specificity. A complete listing of all of these enzymes has been produced by R.J. Roberts and is available at http://rebase.neb.com/rebase/rebase.html

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37263-09-5


1. Roberts, R.J. Restriction enzymes and their isoschizomers. Nucleic Acids Res. 18 (1990) 2331-2365. [PMID: 2159140]

[EC created 1984 from EC 3.1.23 and EC 3.1.24]

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