|PROSITE documentation PDOC00615|
Escherichia coli endonuclease III (EC 220.127.116.11) (gene nth)  is a DNA repair enzyme that acts both as a DNA N-glycosylase, removing oxidized pyrimidines from DNA, and as an apurinic/apyrimidinic (AP) endonuclease, introducing a single-strand nick at the site from which the damaged base was removed. Endonuclease III is an iron-sulfur protein that binds a single 4Fe-4S cluster. The 4Fe-4S cluster does not seem to be important for catalytic activity, but is probably involved in the proper positioning of the enzyme along the DNA strand .
Endonuclease III is evolutionary related to the following proteins:
The 4Fe-4S cluster is bound by four cysteines which are all located in a 17 amino acid region at the C-terminal end of endonuclease III. A similar region is also present in the central section of mutY and in the C-terminus of ORF10 and of the Micrococcus UV endonuclease. The 4Fe-4S cluster region does not exist in YAL015c.
We developed two signature patterns for these proteins: the first corresponds to the core of the iron-sulfur binding domain, the second corresponds to the best conserved region in the catalytic core of these enzymes.Last update:
December 2004 / Pattern and text revised.
PROSITE methods (with tools and information) covered by this documentation:
|1||Authors||Kuo C.-F., McRee D.E., Fisher C.L., O'Handley S.F., Cunningham R.P., Tainer J.A.|
|Title||Atomic structure of the DNA repair [4Fe-4S] enzyme endonuclease III.|
|Title||Crosslinked by a cluster.|
|Source||Curr. Biol. 3:173-174(1993).|
|3||Authors||Roldan-Arjona T., Anselmino C., Lindahl T.|
|Source||Nucleic Acids Res. 24:3307-3312(1996).|
|4||Authors||Noelling J., van Eeden F.J.M., Eggen R.I.L., de Vos W.M.|
|Source||Nucleic Acids Res. 20:6501-6507(1992).|