Biological Assembly 1  

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 294.16 kDa 
• Atom Count: 19,838 
• Modelled Residue Count: 2,486 
• Deposited Residue Count: 2,620 
• Unique protein chains: 1

 4GW9

Structure of a bacteriophytochrome and light-stimulated protomer swapping with a gene repressor

• PDB DOI:  https://doi.org/10.2210/pdb4GW9/pdb
• Entry: 4GW9 supersedes: 4EHO

• Classification: SIGNALING PROTEIN
• Organism(s): Rhodopseudomonas palustris CGA009
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2012-09-01 Released: 2012-09-26 
• Deposition Author(s): Bellini, D., Papiz, M.Z.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.243 
• R-Value Work: 0.200 
• R-Value Observed: 0.202 

Literature

Structure of a bacteriophytochrome and light-stimulated protomer swapping with a gene repressor.

Bellini, D., Papiz, M.Z.

(2012) Structure 20: 1436-1446

• PubMed: 22795083 
• DOI: https://doi.org/10.1016/j.str.2012.06.002
• Primary Citation of Related Structures:  
  4GW9


• PubMed Abstract: 
  

Phytochromes are photoreceptors in phototropic organisms that respond to light conditions by changing interactions between a response regulator and DNA. Bacterial phytochromes (BphPs) comprise an input photosensory core domain (PCD) and an output transducing domain (OTD). We report the structure of a BphP containing both PCD and the majority of its OTD, and demonstrate interaction with its cognate repressor. The OTD of RpBphP1, from Rhodopseudomonas palustris, is composed of a PAS/PAC domain and, to our knowledge, a hitherto unrecognized two-helix output sensor (HOS) domain. Unlike canonical BphPs, it does not transmit phosphorelay signals but forms a complex with the transcriptional repressor RpPpsR2 on photoconversion with far-red light. We show that HOS is essential for complex formation and that the anti-parallel dimer geometry is crucial in achieving HOS domain activation and protomer swapping under the control of light. These results provide insights into the steps taken by a two-component signaling system.

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Organizational Affiliation: 

Institute of Integrative Biology, Biosciences Building, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
bacteriophytochrome	A, B, C, D	655	Rhodopseudomonas palustris CGA009	Mutation(s): 0  Gene Names: RPA1537 EC: 2.7.13.3
UniProt
Find proteins for B3Q7C0 (Rhodopseudomonas palustris (strain TIE-1)) Explore B3Q7C0  Go to UniProtKB:  B3Q7C0

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
BLA	E [auth A], F [auth B], G [auth C], H [auth D]	BILIVERDINE IX ALPHA C33 H34 N4 O6 GWZYPXHJIZCRAJ-SRVCBVSDSA-N

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A, B, C, D	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.243 
• R-Value Work: 0.200 
• R-Value Observed: 0.202 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 102.94	α = 90
b = 146.87	β = 101.17
c = 139.55	γ = 90

Software Package:

Software Name	Purpose
GDA	data collection
SHARP	phasing
REFMAC	refinement
xia2	data reduction
XDS	data reduction
SCALA	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-09-26 
Deposition Author(s): Bellini, D., Papiz, M.Z.
• This entry supersedes: 4EHO

Revision History  

• Version 1.0: 2012-09-26
  Type: Initial release