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The hSNM1 protein is a DNA 5'-exonuclease.

ABSTRACT: The human SNM1 protein is a member of a highly conserved group of proteins catalyzing the hydrolysis of nucleic acid substrates. Although overproduction is unstable in mammalian cells, we have overproduced a recombinant hSNM1 protein in an insect cell system. The protein is a single-strand 5'-exonuclease, like its yeast homolog. The enzyme utilizes either DNA or RNA substrates, requires a 5'-phosphate moiety, shows very little activity on double-strand substrates, and functions at a size consistent with a monomer. The exonuclease activity requires the conserved beta-lactamase domain; site-directed mutagenesis of a conserved aspartate inactivates the exonuclease.

SUBMITTER: Hejna J

PROVIDER: S-EPMC2094091 | biostudies-literature | 2007

REPOSITORIES: biostudies-literature

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The hSNM1 protein is a DNA 5'-exonuclease.

Hejna James J Philip Sahaayaruban S Ott Jesse J Faulkner Craig C Moses Robb R

Nucleic acids research 20070905 18

The human SNM1 protein is a member of a highly conserved group of proteins catalyzing the hydrolysis of nucleic acid substrates. Although overproduction is unstable in mammalian cells, we have overproduced a recombinant hSNM1 protein in an insect cell system. The protein is a single-strand 5'-exonuclease, like its yeast homolog. The enzyme utilizes either DNA or RNA substrates, requires a 5'-phosphate moiety, shows very little activity on double-strand substrates, and functions at a size consist ...[more]

PMID: 17804464

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