The Methanothermobacter thermautotrophicus ExoIII homologue Mth212 is a DNA uridine endonuclease

TY - JOUR

T1 - The Methanothermobacter thermautotrophicus ExoIII homologue Mth212 is a DNA uridine endonuclease

AU - Georg, Jens

AU - Schomacher, Lars

AU - Chong, James P. J.

AU - Majernik, Alan I.

AU - Raabe, Monika

AU - Urlaub, Henning

AU - Mueller, Sabine

AU - Ciirdaeva, Elena

AU - Kramer, Wilfried

AU - Fritz, Hans-Joachim

PY - 2006/10

Y1 - 2006/10

N2 - The genome of Methanothermobacter thermautotrophicus, as a hitherto unique case, is apparently devoid of genes coding for general uracil DNA glycosylases, the universal mediators of base excision repair following hydrolytic deamination of DNA cytosine residues. We have now identified protein Mth212, a member of the ExoIII family of nucleases, as a possible initiator of DNA uracil repair in this organism. This enzyme, in addition to bearing all the enzymological hallmarks of an ExoIII homologue, is a DNA uridine endonuclease (U-endo) that nicks double-stranded DNA at the 5'-side of a 2'-d-uridine residue, irrespective of the nature of the opposing nucleotide. This type of activity has not been described before; it is absent from the ExoIII homologues of Escherichia coli, Homo sapiens and Methanosarcina mazei, all of which are equipped with uracil DNA repair glycosylases. The U-endo activity of Mth212 is served by the same catalytic center as its AP-endo activity.

AB - The genome of Methanothermobacter thermautotrophicus, as a hitherto unique case, is apparently devoid of genes coding for general uracil DNA glycosylases, the universal mediators of base excision repair following hydrolytic deamination of DNA cytosine residues. We have now identified protein Mth212, a member of the ExoIII family of nucleases, as a possible initiator of DNA uracil repair in this organism. This enzyme, in addition to bearing all the enzymological hallmarks of an ExoIII homologue, is a DNA uridine endonuclease (U-endo) that nicks double-stranded DNA at the 5'-side of a 2'-d-uridine residue, irrespective of the nature of the opposing nucleotide. This type of activity has not been described before; it is absent from the ExoIII homologues of Escherichia coli, Homo sapiens and Methanosarcina mazei, all of which are equipped with uracil DNA repair glycosylases. The U-endo activity of Mth212 is served by the same catalytic center as its AP-endo activity.

KW - ARCHAEON PYROBACULUM-AEROPHILUM

KW - ESCHERICHIA-COLI

KW - EXTREME THERMOPHILE

KW - POLYACRYLAMIDE-GELS

KW - GLYCOSYLASE

KW - URACIL

KW - REPAIR

KW - PROTEINS

KW - RESIDUES

KW - INCISION

U2 - 10.1093/nar/gkl604

DO - 10.1093/nar/gkl604

M3 - Article

SN - 0305-1048

VL - 34

SP - 5325

EP - 5336

JO - Nucleic Acids Research

JF - Nucleic Acids Research

IS - 18

ER -