2HQN
Structure of a Atypical Orphan Response Regulator Protein Revealed a New Phosphorylation-Independent Regulatory Mechanism
Summary for 2HQN
| Entry DOI | 10.2210/pdb2hqn/pdb |
| Related | 2HQO 2HQR |
| Descriptor | Putative TRANSCRIPTIONAL REGULATOR (1 entity in total) |
| Functional Keywords | phosporylation-independent response regulator, signaling protein |
| Biological source | Helicobacter pylori |
| Total number of polymer chains | 1 |
| Total formula weight | 12481.29 |
| Authors | |
| Primary citation | Hong, E.,Lee, H.M.,Ko, H.,Kim, D.-U.,Jeon, B.-Y.,Jung, J.,Shin, J.,Lee, S.-A.,Kim, Y.,Jeon, Y.H.,Cheong, C.,Cho, H.-S.,Lee, W. Structure of an Atypical Orphan Response Regulator Protein Supports a New Phosphorylation-independent Regulatory Mechanism J.Biol.Chem., 282:20667-20675, 2007 Cited by PubMed Abstract: Two-component signal transduction systems, commonly found in prokaryotes, typically regulate cellular functions in response to environmental conditions through a phosphorylation-dependent process. A new type of response regulator, hp1043 (HP-RR) from Helicobacter pylori, has been recently identified. HP-RR is essential for cell growth and does not require the well known phosphorelay scheme. Unphosphorylated HP-RR binds specifically to its own promoter (P(1043)) and autoregulates the promoter of the tlpB gene (P(tlpB)). We have determined the structure of HP-RR by NMR and x-ray crystallography, revealing a symmetrical dimer with two functional domains. The molecular topology resembles that of the OmpR/PhoB subfamily, however, the symmetrical dimer is stable even in the unphosphorylated state. The dimer interface, formed by three secondary structure elements (alpha4-beta5-alpha5), resembles that of the active, phosphorylated forms of ArcA and PhoB. Several conserved residues of the HP-RR dimeric interface deviate from the OmpR/PhoB subfamily, although there are similar salt bridges and hydrophobic patches within the interface. Our findings reveal how a new type of response regulator protein could function as a cell growth-associated regulator in the absence of post-translational modification. PubMed: 17491010DOI: 10.1074/jbc.M609104200 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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