7QFZ

BrxR, a WYL-domain containing transcriptional regulator

Summary for 7QFZ

• Entry DOI: 10.2210/pdb7qfz/pdb
• Descriptor: WYL domain-containing protein, SULFATE ION (3 entities in total)
• Functional Keywords: transcription factor, dna binding, phage defence, dna binding protein
• Biological source: Escherichia fergusonii ATCC 35469
• Total number of polymer chains: 8
• Total formula weight: 271747.70

Authors

Picton, D.M.,Blower, T.R. (deposition date: 2021-12-07, release date: 2022-05-18, Last modification date: 2024-05-01)

Primary citation

Picton, D.M.,Harling-Lee, J.D.,Duffner, S.J.,Went, S.C.,Morgan, R.D.,Hinton, J.C.D.,Blower, T.R.
A widespread family of WYL-domain transcriptional regulators co-localizes with diverse phage defence systems and islands.
Nucleic Acids Res., 50:5191-5207, 2022

PubMed Abstract: Bacteria are under constant assault by bacteriophages and other mobile genetic elements. As a result, bacteria have evolved a multitude of systems that protect from attack. Genes encoding bacterial defence mechanisms can be clustered into 'defence islands', providing a potentially synergistic level of protection against a wider range of assailants. However, there is a comparative paucity of information on how expression of these defence systems is controlled. Here, we functionally characterize a transcriptional regulator, BrxR, encoded within a recently described phage defence island from a multidrug resistant plasmid of the emerging pathogen Escherichia fergusonii. Using a combination of reporters and electrophoretic mobility shift assays, we discovered that BrxR acts as a repressor. We present the structure of BrxR to 2.15 Å, the first structure of this family of transcription factors, and pinpoint a likely binding site for ligands within the WYL-domain. Bioinformatic analyses demonstrated that BrxR-family homologues are widespread amongst bacteria. About half (48%) of identified BrxR homologues were co-localized with a diverse array of known phage defence systems, either alone or clustered into defence islands. BrxR is a novel regulator that reveals a common mechanism for controlling the expression of the bacterial phage defence arsenal.

PubMed: 35544231
DOI: 10.1093/nar/gkac334

Experimental method

X-RAY DIFFRACTION (2.15 Å)