Deoxyribonucleases, Type I Site-Specific

**Definition:** Enzyme systems containing three different subunits and requiring ATP, S-adenosylmethionine, and magnesium for endonucleolytic activity to give random double-stranded fragments with terminal 5'-phosphates. They function also as DNA-dependent ATPases and modification methylases, catalyzing the reactions of EC 2.1.1.72 and EC 2.1.1.73 with similar site-specificity. The systems recognize specific short DNA sequences and cleave at sites remote from the recognition sequence. Enzymes from different microorganisms with the same specificity are called isoschizomers. EC 3.1.21.3.

**Tree numbers:** - D08.811.150.280.250 - D08.811.277.352.335.350.300.250 - D08.811.277.352.355.325.300.250

**Synonyms:** - Deoxyribonucleases, Type I, Site-Specific - Type I Site Specific Deoxyribonucleases - Type I Site-Specific Deoxyribonucleases - DNA Restriction Enzymes, Type I - DNase, Site Specific, Type I - Site-Specific DNase, Type I - Type I Site Specific DNase - Type I Site-Specific DNase - DNase, Site-Specific, Type I - Restriction Endonucleases, Type I - Deoxyribonucleases, Type I, Site Specific - Type I Restriction Enzymes