5W4N

Crystal structure of Streptococcus dysgalactiae SHP pheromone receptor Rgg2(C45S)

5W4N の概要

• エントリーDOI: 10.2210/pdb5w4n/pdb
• 関連するPDBエントリー: 4YV6 4YV9 5W4M
• 分子名称: Transcriptional regulator, DIMETHYL SULFOXIDE, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: dna binding, pheromone binding, repeat domain, quorum sensing, dna binding protein, rrnpp
• 由来する生物種: Streptococcus dysgalactiae
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 67538.59

構造登録者

Neiditch, M.B.,Khataokar, A.A.,Capodagli, G.C. (登録日: 2017-06-12, 公開日: 2017-10-25, 最終更新日: 2023-10-04)

主引用文献

Wilkening, R.V.,Capodagli, G.C.,Khataokar, A.,Tylor, K.M.,Neiditch, M.B.,Federle, M.J.
Activating mutations in quorum-sensing regulator Rgg2 and its conformational flexibility in the absence of an intermolecular disulfide bond.
J. Biol. Chem., 292:20544-20557, 2017

PubMed Abstract: Rap/Rgg/NprR/PlcR/PrgX (RRNPP) quorum-sensing systems use extracellular peptide pheromones that are detected by cytoplasmic receptors to regulate gene expression in firmicute bacteria. Rgg-type receptors are allosterically regulated through direct pheromone binding to control transcriptional activity; however, the receptor activation mechanism remains poorly understood. Previous work has identified a disulfide bond between Cys-45 residues within the homodimer interface of Rgg2 from (Rgg2). Here, we compared two Rgg2(C45S) X-ray crystal structures with that of wild-type Rgg2 and found that in the absence of the intermolecular disulfide, the Rgg2 dimer interface is destabilized and Rgg2 can adopt multiple conformations. One conformation closely resembled the "disulfide-locked" Rgg2 secondary and tertiary structures, but another displayed more extensive rigid-body shifts as well as dramatic secondary structure changes. In parallel experiments, a genetic screen was used to identify mutations in of ( ) that conferred pheromone-independent transcriptional activation of an Rgg2-stimulated promoter. Eight mutations yielding constitutive Rgg2 activity, designated Rgg2*, were identified, and five of them clustered in or near an Rgg2 region that underwent conformational changes in one of the Rgg2(C45S) crystal structures. The Rgg2* mutations increased Rgg2 sensitivity to pheromone and pheromone variants while displaying decreased sensitivity to the Rgg2 antagonist cyclosporine A. We propose that Rgg2* mutations invoke shifts in free-energy bias to favor the active state of the protein. Finally, we present evidence for an electrostatic interaction between an N-terminal Asp of the pheromone and Arg-153 within the proposed pheromone-binding pocket of Rgg2.

PubMed: 29030429
DOI: 10.1074/jbc.M117.801670

実験手法

X-RAY DIFFRACTION (2.198 Å)