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Updated: Jul 15, 2026

From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins
Published on: July 4, 2016
Crystal structure of the apo-PerR-Zn protein from Bacillus subtilis
Daouda A K Traoré1, Abdelnasser El Ghazouani, Sougandi Ilango
1DRDC/Laboratoire de Physicochimie des Métaux en Biologie, UMR 5155 CEA-CNRS-UJF, CEA-Grenoble, 38054 Grenoble Cedex 9, France.
Abstract:
Bacteria adapt to elevated levels of Reactive Oxygen Species (ROS) by increasing the expression of defence and repair proteins, which is regulated by ROS responsive transcription factors. In Bacillus subtilis the zinc protein PerR, a peroxide sensor that binds DNA in the presence of a regulatory metal Mn2+ or Fe2+, mediates the adaptive response to H2O2. This study presents the first crystal structure of apo-PerR-Zn which shows that all four cysteine residues of the protein are involved in zinc co-ordination. The Zn(Cys)4 site locks the dimerization domain and stabilizes the dimer. Sequence alignment of PerR-like proteins supports that this structural site may constitute a distinctive feature of this class of peroxide stress regulators.
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