4UAR

Crystal structure of apo-CbbY from Rhodobacter sphaeroides


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.200 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Degradation of potent Rubisco inhibitor by selective sugar phosphatase.

Bracher, A.Sharma, A.Starling-Windhof, A.Hartl, F.U.Hayer-Hartl, M.

(2015) Nat Plants 1: 14002-14002

  • DOI: 10.1038/nplants.2014.2
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyses the conversion of atmospheric carbon dioxide into organic compounds in photosynthetic organisms. Alongside carboxylating the five-carbon sugar ribulose-1,5-bisphosphate (RuBP)(1-3), ...

    Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyses the conversion of atmospheric carbon dioxide into organic compounds in photosynthetic organisms. Alongside carboxylating the five-carbon sugar ribulose-1,5-bisphosphate (RuBP)(1-3), Rubisco produces a small amount of xylulose-1,5-bisphosphate (XuBP), a potent inhibitor of Rubisco(4). The AAA+ protein Rubisco activase removes XuBP from the active site of Rubisco in an ATP-dependent process(5,6). However, free XuBP rapidly rebinds to Rubisco, perpetuating its inhibitory effect. Here, we combine biochemical and structural analyses to show that the CbbY protein of the photosynthetic bacterium Rhodobacter sphaeroides and Arabidopsis thaliana is a highly selective XuBP phosphatase. We also show that CbbY converts XuBP to the non-inhibitory compound xylulose-5-phosphate, which is recycled back to RuBP. We solve the crystal structures of CbbY from R. sphaeroides and A. thaliana, and through mutational analysis show that the cap domain of the protein confers the selectivity for XuBP over RuBP. Finally, in vitro experiments with CbbY from R. sphaeroides reveal that CbbY cooperates with Rubisco activase to prevent a detrimental build-up of XuBP at the Rubisco active site. We suggest that CbbY, which is conserved in algae and plants, is an important component of the cellular machinery that has evolved to deal with the shortcomings of the ancient enzyme Rubisco.


    Organizational Affiliation

    Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Protein CbbY
A
230Rhodobacter sphaeroidesMutation(s): 0 
Gene Names: cbbY
EC: 3.1.3
Find proteins for P95649 (Rhodobacter sphaeroides)
Go to UniProtKB:  P95649
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download CCD File 
A
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.200 
  • Space Group: I 4
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 117.685α = 90
b = 117.685β = 90
c = 43.994γ = 90
Software Package:
Software NamePurpose
SCALAdata scaling
RESOLVEmodel building
PDB_EXTRACTdata extraction
REFMACrefinement
XDSdata reduction
SCALAdata scaling
SHARPphasing
XSCALEdata reduction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-12-31
    Type: Initial release
  • Version 1.1: 2016-06-15
    Changes: Database references