3TGN

Crystal Structure of the zinc-dependent MarR Family Transcriptional Regulator AdcR in the Zn(II)-bound State

Summary for 3TGN

• Entry DOI: 10.2210/pdb3tgn/pdb
• Descriptor: Adc operon repressor AdcR, ZINC ION (3 entities in total)
• Functional Keywords: helix-turn-helix, transcriptional regulator, transcription
• Biological source: Streptococcus pneumoniae
• Total number of polymer chains: 2
• Total formula weight: 33519.46

Authors

Guerra, A.J.,Dann III, C.E.,Giedroc, D.P. (deposition date: 2011-08-17, release date: 2011-11-30, Last modification date: 2024-02-28)

Primary citation

Guerra, A.J.,Dann, C.E.,Giedroc, D.P.
Crystal Structure of the Zinc-Dependent MarR Family Transcriptional Regulator AdcR in the Zn(II)-Bound State.
J.Am.Chem.Soc., 133:19614-19617, 2011

PubMed Abstract: Streptococcus pneumoniae adhesin competence regulator (AdcR), the first metal-dependent member of the multiple antibiotic resistance regulator (MarR) family of proteins, represses the transcription of a high-affinity zinc-specific uptake transporter, a group of surface antigen zinc-binding pneumococcal histidine triad proteins (PhtA, PhtB, PhtD, and PhtE), and an AdcA homologue (AdcAII). The 2.0 Å resolution structure of Zn(II)-bound AdcR reveals a highly helical two-fold-symmetric dimer with two distinct metal-binding sites per protomer. Zn(II) is tetrahedrally coordinated by E24, H42, H108, and H112 in what defines the primary sensing site in AdcR. Site 2 is a tetracoordinate site whose function is currently unknown. NMR methyl group perturbation experiments reveal that Zn(II) drives a global change in the structure of apo-AdcR that stabilizes a conformation that is compatible with DNA binding. This co-repression mechanism is unprecedented in MarR transcriptional regulators.

PubMed: 22085181
DOI: 10.1021/ja2080532

Experimental method

X-RAY DIFFRACTION (2 Å)