6O8L
Crystal Structure of C9S apo and reduced Sulfide-responsive transcriptional repressor (SqrR) from Rhodobacter capsulatus.
Summary for 6O8L
Entry DOI | 10.2210/pdb6o8l/pdb |
Descriptor | Transcriptional regulator, ArsR family (2 entities in total) |
Functional Keywords | transcription factor, sulfide sensor, reactive sulfur species, photosynthesis regulation, transcription |
Biological source | Rhodobacter capsulatus |
Total number of polymer chains | 1 |
Total formula weight | 12311.89 |
Authors | Capdevila, D.A.,Gonzalez-Gutierrez, G.,Giedroc, D.P. (deposition date: 2019-03-11, release date: 2020-04-01, Last modification date: 2023-10-11) |
Primary citation | Capdevila, D.A.,Walsh, B.J.C.,Zhang, Y.,Dietrich, C.,Gonzalez-Gutierrez, G.,Giedroc, D.P. Structural basis for persulfide-sensing specificity in a transcriptional regulator. Nat.Chem.Biol., 17:65-70, 2021 Cited by PubMed Abstract: Cysteine thiol-based transcriptional regulators orchestrate the coordinated regulation of redox homeostasis and other cellular processes by 'sensing' or detecting a specific redox-active molecule, which in turn activates the transcription of a specific detoxification pathway. The extent to which these sensors are truly specific in cells for a singular class of reactive small-molecule stressors, for example, reactive oxygen or sulfur species, is largely unknown. Here, we report structural and mechanistic insights into the thiol-based transcriptional repressor SqrR, which reacts exclusively with oxidized sulfur species such as persulfides, to yield a tetrasulfide bridge that inhibits DNA operator-promoter binding. Evaluation of crystallographic structures of SqrR in various derivatized states, coupled with the results of a mass spectrometry-based kinetic profiling strategy, suggest that persulfide selectivity is determined by structural frustration of the disulfide form. These findings led to the identification of an uncharacterized repressor from the bacterial pathogen Acinetobacter baumannii as a persulfide sensor. PubMed: 33106663DOI: 10.1038/s41589-020-00671-9 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.36 Å) |
Structure validation
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