Structural insight into DNA recognition by bacterial transcriptional regulators of the SorC/DeoR family
Marketa Soltysova, Irena Sieglova, Milan Fabry, Jirı Brynda, Jana Skerlova
and Pavlına Rezacova [1]
Molecular Tour
SorC (SorC/DeoR) protein family (Pfam family Sugar-bind: PF04198, (1) ) is one of the large families of bacterial transcriptional regulators, predominantly repressors, that are known for their roles in the regulation of carbohydrate metabolism and quorum-sensing in more than 2,500 bacterial species. For example, among the most studied members are CggR (2-4) or LsrR (5,6). SorC protomers consist of a large C terminal effector binding domain (EBD) and a much smaller N terminal DNA binding domain (DBD). As an assembly, SorC proteins work as tetramers in a cooperative manner, to our best knowledge (4,7).
So far (2021), several 3D structures of SorC EBDs have been determined. They belong to the so-called NagB-like family for their homology with glucosamine 6 phosphate deaminases from the NagB family, characterized by the central Rossman fold (3,8,9). On the other hand, information on the structure of DNA-binding domains of SorC-family proteins is rather limited. SorC DBDs belong to the most abundant helix turn helix (HTH) superfamily and, by their sequences and structures, they cluster into two subfamilies: SorC/DeoR and SorC/CggR.
SorC/DeoR DBD is smaller and consists of the HTH bundle followed by a "β linker" (9), and the bigger SorC/CggR belong to the winged HTH family (10).
In this paper, we present the first structure of SorC DBDs bound to DNA duplexes. We show DBD structures of representatives of each subfamily, DeoR and CggR, and compare their binding mode, which is likely common to all SorC family members.
References:
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References
- ↑ Soltysova M, Sieglova I, Fabry M, Brynda J, Skerlova J, Rezacova P. Structural insight into DNA recognition by bacterial transcriptional regulators of the SorC/DeoR family. Acta Crystallogr D Struct Biol. 2021 Nov 1;77(Pt 11):1411-1424. doi:, 10.1107/S2059798321009633. Epub 2021 Oct 20. PMID:34726169 doi:http://dx.doi.org/10.1107/S2059798321009633
