Enzymes that hydrolyze phosphodiester bonds, used in various molecular biology applications.
Properties of deoxyribonucleases (DNases)
|Nuclease||Applications||Substrate||Specificity, polarity of cleavage||Reaction products|
|DNase I, RNase-free|
DNase I, RNase-free with MnCl2
DNase I, RNase-free, HC
DNA in RNA-DNA
|Sequence and base unspecific|
|Endonuclease IV, E. coli (Endo IV)||AP DNA||5' to an abasic site, 3'→ 5' exonuclease|
|Endonuclease V, T. maritima (Endo V)||Deaminated DNA||Second phosphodiester bond 3' to the lesion|
|Exonuclease I (Exo I)||ssDNA3||3'→ 5'|
|Exonuclease III (Exo III)||dsDNA (with nicks,|
blunt ends, 5’-overhangs)4
|AP DNA||5' to an abasic site|
|DNA with 3’-phosphorylated|
|Exonuclease VII||ssDNA3||3'→ 5'|
|Exonuclease, T7 Gene 6||dsDNA and RNA:DNA hybrids||5'→ 3'|
1 - ssDNA is cleaved slower than dsDNA.
2 - when enzyme is in excess, complimentary strand is also nicked, generating a double-stranded break.
3 - does not cleave DNA chains with terminal 3'-phosphoryl or acetyl groups. Not suitable for removing 3'- overhang ends of dsDNA - this activity is greatly reduced.
4 - not active on 3'-overhang ends of DNA that are at least 4 base long or on phosphorothioate-linked nucleotides or ssDNA.
5 - selectively digests the 5'-phosphorylated strand of dsDNA. Exhibits greatly reduced activity on ssDNA and non-phosphorylated DNA; has limited activity at gaps in DNA and no activity at nicks.
For Research Use Only. Not for use in diagnostic procedures.