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NurA, a novel 5'-3' nuclease gene linked to rad50 and mre11 homologs of thermophilic Archaea.

ABSTRACT: We isolated and characterized a new nuclease (NurA) exhibiting both single-stranded endonuclease activity and 5'-3' exonuclease activity on single-stranded and double-stranded DNA from the hyperthermophilic archaeon Sulfolobus acidocaldarius. Nuclease homologs are detected in all thermophilic archaea and, in most species, the nurA gene is organized in an operon-like structure with rad50 and mre11 archaeal homologs. This nuclease might thus act in concert with Rad50 and Mre11 proteins in archaeal recombination/repair. To our knowledge, this is the first report of a 5'-3' nuclease potentially associated with Rad50 and Mre11-like proteins that may lead to the processing of double-stranded breaks in 3' single-stranded tails.

SUBMITTER: Constantinesco F

PROVIDER: S-EPMC1084146 | biostudies-literature | 2002 Jun

REPOSITORIES: biostudies-literature

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NurA, a novel 5'-3' nuclease gene linked to rad50 and mre11 homologs of thermophilic Archaea.

Constantinesco Florence F Forterre Patrick P Elie Christiane C

EMBO reports 20020601 6

We isolated and characterized a new nuclease (NurA) exhibiting both single-stranded endonuclease activity and 5'-3' exonuclease activity on single-stranded and double-stranded DNA from the hyperthermophilic archaeon Sulfolobus acidocaldarius. Nuclease homologs are detected in all thermophilic archaea and, in most species, the nurA gene is organized in an operon-like structure with rad50 and mre11 archaeal homologs. This nuclease might thus act in concert with Rad50 and Mre11 proteins in archaeal ...[more]

PMID: 12052775

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