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DNA uracil repair initiated by the archaeal ExoIII homologue Mth212 via direct strand incision.

ABSTRACT: No genes for any of the known uracil DNA glycosylases of the UDG superfamily are present in the genome of Methanothermobacter thermautotrophicus DeltaH, making it difficult to imagine how DNA-U repair might be initiated in this organism. Recently, Mth212, the ExoIII homologue of M. thermautotrophicus DeltaH has been characterized as a DNA uridine endonuclease, which suggested the possibility of a novel endonucleolytic entry mechanism for DNA uracil repair. With no system of genetic experimentation available, the problem was approached biochemically. Assays of DNA uracil repair in vitro, promoted by crude cellular extracts, provide unequivocal confirmation that this mechanism does indeed operate in M. thermautotrophicus DeltaH.

SUBMITTER: Schomacher L

PROVIDER: S-EPMC2673441 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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DNA uracil repair initiated by the archaeal ExoIII homologue Mth212 via direct strand incision.

Schomacher Lars L Chong James P J JP McDermott Paul P Kramer Wilfried W Fritz Hans-Joachim HJ

Nucleic acids research 20090224 7

No genes for any of the known uracil DNA glycosylases of the UDG superfamily are present in the genome of Methanothermobacter thermautotrophicus DeltaH, making it difficult to imagine how DNA-U repair might be initiated in this organism. Recently, Mth212, the ExoIII homologue of M. thermautotrophicus DeltaH has been characterized as a DNA uridine endonuclease, which suggested the possibility of a novel endonucleolytic entry mechanism for DNA uracil repair. With no system of genetic experimentati ...[more]

PMID: 19240141

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Excision of uracil from DNA by hSMUG1 includes strand incision and processing.

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