4XWJ

Histidine-containing phosphocarrier protein (HPr) and antisigma factor Rsd complex

Summary for 4XWJ

• Entry DOI: 10.2210/pdb4xwj/pdb
• Descriptor: Regulator of sigma D, Phosphocarrier protein HPr (3 entities in total)
• Functional Keywords: anti sigma 70 factor, transcription-transferase complex, transcription/transferase
• Biological source: Escherichia coli (strain K12); More
• Total number of polymer chains: 2
• Total formula weight: 28657.34

Authors

Um, S.H.,Seok, Y.J.,Ha, N.C. (deposition date: 2015-01-29, release date: 2015-10-21, Last modification date: 2024-03-20)

Primary citation

Park, Y.H.,Um, S.H.,Song, S.,Seok, Y.J.,Ha, N.C.
Structural basis for the sequestration of the anti-sigma (70) factor Rsd from sigma (70) by the histidine-containing phosphocarrier protein HPr.
Acta Crystallogr.,Sect.D, 71:1998-2008, 2015

PubMed Abstract: Histidine-containing phosphocarrier protein (HPr) is a general component of the bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) involved in the phosphorylation-coupled transport of numerous sugars called PTS sugars. HPr mainly exists in a dephosphorylated form in the presence of PTS sugars in the medium, while its phosphorylation increases in the absence of PTS sugars. A recent study revealed that the dephosphorylated form of HPr binds and antagonizes the function of the antisigma factor Rsd. This anti-sigma factor sequesters the housekeeping sigma factor σ(70) to facilitate switching of the sigma subunit on RNA polymerase from σ(70) to the stress-responsive sigma factor σ(S) in stationary-phase cells. In this study, the structure of the complex of Rsd and HPr was determined at 2.1 Å resolution and revealed that the binding site for HPr on the surface of Rsd partly overlaps with that for σ(70). The localization of the phosphorylation site on HPr at the binding interface for Rsd explains why phosphorylation of HPr abolishes its binding to Rsd. The mutation of crucial residues involved in the HPr-Rsd interaction significantly influenced the competition between HPr and σ(70) for binding to Rsd both in vitro and in vivo. The results provide a structural basis for the linkage of global gene regulation to nutrient availability in the external environment.

PubMed: 26457424
DOI: 10.1107/S1399004715013759

Experimental method

X-RAY DIFFRACTION (2.095 Å)