Structural basis for cooperative DNA binding by two dimers of the multidrug‐binding protein QacR

@article{Schumacher2002StructuralBF,
  title={Structural basis for cooperative DNA binding by two dimers of the multidrug‐binding protein QacR},
  author={Maria A. Schumacher and Marshall C. Miller and Steve Grkovic and Melissa H. Brown and Ronald A. Skurray and Richard G. Brennan},
  journal={The EMBO Journal},
  year={2002},
  volume={21}
}
The Staphylococcus aureus multidrug‐binding protein QacR represses transcription of the qacA multidrug transporter gene and is induced by multiple structurally dissimilar drugs. QacR is a member of the TetR/CamR family of transcriptional regulators, which share highly homologous N‐terminal DNA‐binding domains connected to seemingly non‐homologous ligand‐binding domains. Unlike other TetR members, which bind ∼15 bp operators, QacR recognizes an unusually long 28 bp operator, IR1, which it… 

Thermodynamics of Cooperative DNA Recognition at a Replication Origin and Transcription Regulatory Site

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Structural mechanism of the simultaneous binding of two drugs to a multidrug‐binding protein

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Biochemical characterization of the multidrug regulator QacR distinguishes residues that are crucial to multidrug binding and induction of qacA transcription.

The functional significance of hydrophobic, aromatic, and polar residues characteristic of the rhodamine 6G pocket and the proximal Tyr(92), proposed to facilitate the transcriptionally active conformation, was examined and highlights the significant contribution of these residues to QacR-mediated derepression of qacA transcription following ligand binding in the distal subpocket and may be important for the general mechanism irrespective of the ligand bound.

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The protein–DNA contacts in RutR·carAB operator complexes

A model of the RutR·operator DNA complex based on the crystal structures of RutR and of the DNA-bound family member QacR is built and tested with site-directed mutagenesis of the helix–turn–helix DNA binding motif and in vitro binding studies with the cognate purified mutant RutR proteins.

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Structural and functional basis of transcriptional regulation by TetR family protein CprB from S. coelicolor A3(2)

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