6ZII

Structure of the isolated REC domain of RcsB from Salmonella enterica serovar Typhimurium in the presence of phosphomimetic BeF3-

Summary for 6ZII

• Entry DOI: 10.2210/pdb6zii/pdb
• Descriptor: Transcriptional regulatory protein RcsB, MAGNESIUM ION (3 entities in total)
• Functional Keywords: response regulator, phosphorylation, two-component systems, transcriptional factor, dna binding protein
• Biological source: Salmonella typhimurium
• Total number of polymer chains: 2
• Total formula weight: 31585.22

Authors

Huesa, J.,Marina, A.,Casino, P. (deposition date: 2020-06-26, release date: 2021-02-17, Last modification date: 2024-11-13)

Primary citation

Huesa, J.,Giner-Lamia, J.,Pucciarelli, M.G.,Paredes-Martinez, F.,Portillo, F.G.,Marina, A.,Casino, P.
Structure-based analyses of Salmonella RcsB variants unravel new features of the Rcs regulon.
Nucleic Acids Res., 49:2357-2374, 2021

PubMed Abstract: RcsB is a transcriptional regulator that controls expression of numerous genes in enteric bacteria. RcsB accomplishes this role alone or in combination with auxiliary transcriptional factors independently or dependently of phosphorylation. To understand the mechanisms by which RcsB regulates such large number of genes, we performed structural studies as well as in vitro and in vivo functional studies with different RcsB variants. Our structural data reveal that RcsB binds promoters of target genes such as rprA and flhDC in a dimeric active conformation. In this state, the RcsB homodimer docks the DNA-binding domains into the major groove of the DNA, facilitating an initial weak read-out of the target sequence. Interestingly, comparative structural analyses also show that DNA binding may stabilize an active conformation in unphosphorylated RcsB. Furthermore, RNAseq performed in strains expressing wild-type or several RcsB variants provided new insights into the contribution of phosphorylation to gene regulation and assign a potential role of RcsB in controlling iron metabolism. Finally, we delimited the RcsB box for homodimeric active binding to DNA as the sequence TN(G/A)GAN4TC(T/C)NA. This RcsB box was found in promoter, intergenic and intragenic regions, facilitating both increased or decreased gene transcription.

PubMed: 33638994
DOI: 10.1093/nar/gkab060

Experimental method

X-RAY DIFFRACTION (2.5 Å)