Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 22.96 kDa 
• Atom Count: 1826 
• Residue Count: 204 
• Unique protein chains: 2

1U0S

Chemotaxis kinase CheA P2 domain in complex with response regulator CheY from the thermophile thermotoga maritima

• DOI: 10.2210/pdb1U0S/pdb

• Classification: SIGNALING PROTEIN
• Organism(s): Thermotoga maritima
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2004-07-14 Released: 2004-08-10 
• Deposition Author(s): Park, S.Y., Beel, B.D., Simon, M.I., Bilwes, A.M., Crane, B.R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.253 
• R-Value Work: 0.227 
• R-Value Observed: 0.230 

Literature

In different organisms, the mode of interaction between two signaling proteins is not necessarily conserved

Park, S.Y., Beel, B.D., Simon, M.I., Bilwes, A.M., Crane, B.R.

(2004) Proc Natl Acad Sci U S A 101: 11646-11651

• PubMed: 15289606 
• DOI: 10.1073/pnas.0401038101
• Primary Citation of Related Structures:  
  1U0S


• PubMed Abstract: 
  

Although interfaces mediating protein-protein interactions are thought to be under strong evolutionary constraints, binding of the chemotaxis histidine kinase CheA to its phosphorylation target CheY suggests otherwise. The structure of Thermotoga maritima CheA domain P2 in complex with CheY reveals a different association than that observed for the same Escherichia coli proteins. Similar regions of CheY bind CheA P2 in the two systems, but the CheA P2 domains differ by an approximately 90 degrees rotation. CheA binds CheY with identical affinity in T. maritima and E. coli at the vastly different temperatures where the respective organisms live. Distinct sets of P2 residues mediate CheY binding in the two complexes; conservation patterns of these residues in CheA and compensations in CheY delineate two families of prokaryotic chemotaxis systems. A protein complex that has the same components and general function in different organisms, but an altered structure, indicates unanticipated complexity in the evolution of protein-protein interactions and cautions against extrapolating structural data from homologs.

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Organizational Affiliation: 

Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14850, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Chemotaxis protein cheY	Y	118	Thermotoga maritima	Mutation(s): 0  Gene Names: cheY
Find proteins for Q56312 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)) Explore Q56312  Go to UniProtKB:  Q56312

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Chemotaxis protein cheA	A	86	Thermotoga maritima	Mutation(s): 0  Gene Names: cheA EC: 2.7.3 (PDB Primary Data), 2.7.13.3 (UniProt)
Find proteins for Q56310 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)) Explore Q56310  Go to UniProtKB:  Q56310

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.253 
• R-Value Work: 0.227 
• R-Value Observed: 0.230 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 88.55	α = 90
b = 91.43	β = 90
c = 31.66	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
EPMR	phasing
CNS	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2004-07-14 
• Released Date: 2004-08-10 
Deposition Author(s): Park, S.Y., Beel, B.D., Simon, M.I., Bilwes, A.M., Crane, B.R.

Revision History 

• Version 1.0: 2004-08-10
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance