3F8C

Crystal structure of multidrug binding transcriptional regulator LmrR complexed with Hoechst 33342

3F8C の概要

• エントリーDOI: 10.2210/pdb3f8c/pdb
• 関連するPDBエントリー: 3F8B 3F8F
• 分子名称: Transcriptional regulator, PadR-like family, 2'-(4-ETHOXYPHENYL)-5-(4-METHYL-1-PIPERAZINYL)-2,5'-BI-BENZIMIDAZOLE (3 entities in total)
• 機能のキーワード: winged helix turn helix, transcription regulator
• 由来する生物種: Lactococcus lactis subsp. cremoris
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 15217.34

構造登録者

Madoori, P.K.,Agustiandari, H.,Driessen, A.J.M.,Thunnissen, A.-M.W.H. (登録日: 2008-11-12, 公開日: 2008-12-30, 最終更新日: 2023-11-01)

主引用文献

Madoori, P.K.,Agustiandari, H.,Driessen, A.J.,Thunnissen, A.M.
Structure of the transcriptional regulator LmrR and its mechanism of multidrug recognition.
Embo J., 28:156-166, 2009

PubMed Abstract: LmrR is a PadR-related transcriptional repressor that regulates the production of LmrCD, a major multidrug ABC transporter in Lactococcus lactis. Transcriptional regulation is presumed to follow a drug-sensitive induction mechanism involving the direct binding of transporter ligands to LmrR. Here, we present crystal structures of LmrR in an apo state and in two drug-bound states complexed with Hoechst 33342 and daunomycin. LmrR shows a common topology containing a typical beta-winged helix-turn-helix domain with an additional C-terminal helix involved in dimerization. Its dimeric organization is highly unusual with a flat-shaped hydrophobic pore at the dimer centre serving as a multidrug-binding site. The drugs bind in a similar manner with their aromatic rings sandwiched in between the indole groups of two dimer-related tryptophan residues. Multidrug recognition is facilitated by conformational plasticity and the absence of drug-specific hydrogen bonds. Combined analyses using site-directed mutagenesis, fluorescence-based drug binding and protein-DNA gel shift assays reveal an allosteric coupling between the multidrug- and DNA-binding sites of LmrR that most likely has a function in the induction mechanism.

PubMed: 19096365
DOI: 10.1038/emboj.2008.263

実験手法

X-RAY DIFFRACTION (2.2 Å)