5V30

Crystal structure of the sensor domain of the transcriptional regulator HcpR from Porphyromonas Gingivalis

Summary for 5V30

• Entry DOI: 10.2210/pdb5v30/pdb
• Descriptor: Transcriptional regulator, GLYCEROL, SULFATE ION, ... (4 entities in total)
• Functional Keywords: beta barrel, dimerization helix, transcriptional regulator, heme binding protein, transcription
• Biological source: Porphyromonas gingivalis
• Total number of polymer chains: 2
• Total formula weight: 34958.77

Authors

Musayev, F.N.,Belvin, B.R.,Escalante, C.R.,Turner, J.,Lewis, J.P. (deposition date: 2017-03-06, release date: 2018-06-13, Last modification date: 2024-05-22)

Primary citation

Belvin, B.R.,Musayev, F.N.,Burgner, J.,Scarsdale, J.N.,Escalante, C.R.,Lewis, J.P.
Nitrosative stress sensing in Porphyromonas gingivalis: structure of and heme binding by the transcriptional regulator HcpR.
Acta Crystallogr D Struct Biol, 75:437-450, 2019

PubMed Abstract: Although the HcpR regulator plays a vital step in initiation of the nitrosative stress response in many Gram-negative anaerobic bacteria, the molecular mechanisms that it uses to mediate gas sensing are not well understood. Here, a 2.6 Å resolution crystal structure of the N-terminal sensing domain of the anaerobic periodontopathogen Porphyromonas gingivalis HcpR is presented. The protein has classical features of the regulators belonging to the FNR-CRP family and contains a hydrophobic pocket in its N-terminal sensing domain. It is shown that heme bound to HcpR exhibits heme iron as a hexacoordinate system in the absence of nitric oxide (NO) and that upon nitrosylation it transitions to a pentacoordinate system. Finally, small-angle X-ray scattering experiments on full-length HcpR reveal that the C-terminal DNA-binding domain of HcpR has a high degree of interdomain flexibility.

PubMed: 30988260
DOI: 10.1107/S205979831900264X

Experimental method

X-RAY DIFFRACTION (3.15 Å)