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NikR is a ribbon-helix-helix DNA-binding protein.

ABSTRACT: Escherichia coli NikR, a repressor with homologs in other bacteria and archaea, was identified as a potential new member of the ribbon-helix-helix (beta-alpha-alpha) family of transcription factors in profile based sequence searches and in structure prediction experiments. Biophysical and biochemical characterization of the N-terminal domain of NikR show that it has many features expected of a beta-alpha-alpha protein including alpha-helical content, dimeric solution form, concentration dependent thermal stability, and ability to bind DNA in sequence-specific manner. Mutation of a residue predicted to be important for DNA-binding reduces operator affinity but does not affect the secondary structure or stability of the protein.

SUBMITTER: Chivers PT

PROVIDER: S-EPMC2144182 | biostudies-other | 1999 Nov

REPOSITORIES: biostudies-other

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NikR is a ribbon-helix-helix DNA-binding protein.

Chivers P T PT Sauer R T RT

Protein science : a publication of the Protein Society 19991101 11

Escherichia coli NikR, a repressor with homologs in other bacteria and archaea, was identified as a potential new member of the ribbon-helix-helix (beta-alpha-alpha) family of transcription factors in profile based sequence searches and in structure prediction experiments. Biophysical and biochemical characterization of the N-terminal domain of NikR show that it has many features expected of a beta-alpha-alpha protein including alpha-helical content, dimeric solution form, concentration dependen ...[more]

PMID: 10595554

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