7F9H
complex structure of EnrR-DNA
Summary for 7F9H
Entry DOI | 10.2210/pdb7f9h/pdb |
Descriptor | EnrR repressor, target DNA (3 entities in total) |
Functional Keywords | enrr, repressor, dna complex, dna binding protein |
Biological source | Edwardsiella piscicida More |
Total number of polymer chains | 4 |
Total formula weight | 34399.20 |
Authors | Gan, J.H.,Wang, Q.Y. (deposition date: 2021-07-04, release date: 2022-05-11, Last modification date: 2024-11-13) |
Primary citation | Ma, R.,Liu, Y.,Gan, J.,Qiao, H.,Ma, J.,Zhang, Y.,Bu, Y.,Shao, S.,Zhang, Y.,Wang, Q. Xenogeneic nucleoid-associated EnrR thwarts H-NS silencing of bacterial virulence with unique DNA binding. Nucleic Acids Res., 50:3777-3798, 2022 Cited by PubMed Abstract: Type III and type VI secretion systems (T3/T6SS) are encoded in horizontally acquired genomic islands (GIs) that play crucial roles in evolution and virulence in bacterial pathogens. T3/T6SS expression is subjected to tight control by the host xenogeneic silencer H-NS, but how this mechanism is counteracted remains to be illuminated. Here, we report that xenogeneic nucleoid-associated protein EnrR encoded in a GI is essential for virulence in pathogenic bacteria Edwardsiella and Salmonella. We showed that EnrR plays critical roles in T3/T6SS expression in these bacteria. Various biochemical and genetic analyses demonstrated that EnrR binds and derepresses the promoter of esrB, the critical regulator of T3/T6SS, to promote their expression by competing with H-NS. Additionally, EnrR targets AT-rich regions, globally modulates the expression of ∼363 genes and is involved in various cellular processes. Crystal structures of EnrR in complex with a specific AT-rich palindromic DNA revealed a new DNA-binding mode that involves conserved HTH-mediated interactions with the major groove and contacts of its N-terminal extension to the minor groove in the symmetry-related duplex. Collectively, these data demonstrate that EnrR is a virulence activator that can antagonize H-NS, highlighting a unique mechanism by which bacterial xenogeneic regulators recognize and regulate foreign DNA. PubMed: 35325196DOI: 10.1093/nar/gkac180 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.78 Å) |
Structure validation
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