Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Homo 2-mer - A2 

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

Macromolecule Content

• Total Structure Weight: 85.33 kDa 
• Atom Count: 5976 
• Modelled Residue Count: 738 
• Deposited Residue Count: 758 
• Unique protein chains: 1

1B3Q

CRYSTAL STRUCTURE OF CHEA-289, A SIGNAL TRANSDUCING HISTIDINE KINASE

• DOI: 10.2210/pdb1B3Q/pdb

• Classification: TRANSFERASE
• Organism(s): Thermotoga maritima
• Expression System: Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 1998-12-14 Released: 1999-12-15 
• Deposition Author(s): Bilwes, A.M., Alex, L.A., Crane, B.R., Simon, M.I.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 0.285 
• R-Value Work: 0.213 

Literature

Structure of CheA, a signal-transducing histidine kinase.

Bilwes, A.M., Alex, L.A., Crane, B.R., Simon, M.I.

(1999) Cell 96: 131-141

• PubMed: 9989504 
• DOI: 10.1016/s0092-8674(00)80966-6
• Primary Citation of Related Structures:  
  1B3Q


• PubMed Abstract: 
  

Histidine kinases allow bacteria, plants, and fungi to sense and respond to their environment. The 2.6 A resolution crystal structure of Thermotoga maritima CheA (290-671) histidine kinase reveals a dimer where the functions of dimerization, ATP binding, and regulation are segregated into domains. The kinase domain is unlike Ser/Thr/Tyr kinases but resembles two ATPases, Gyrase B and Hsp90. Structural analogies within this superfamily suggest that the P1 domain of CheA provides the nucleophilic histidine and activating glutamate for phosphotransfer. The regulatory domain, which binds the homologous receptor-coupling protein CheW, topologically resembles two SH3 domains and provides different protein recognition surfaces at each end. The dimerization domain forms a central four-helix bundle about which the kinase and regulatory domains pivot on conserved hinges to modulate transphosphorylation. Different subunit conformations suggest that relative domain motions link receptor response to kinase activity.

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Organizational Affiliation: 

Department of Biology, California Institute of Technology, Pasadena 91125, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (CHEMOTAXIS PROTEIN CHEA)	A, B	379	Thermotoga maritima	Mutation(s): 3  EC: 2.7.3 (PDB Primary Data), 2.7.13.3 (UniProt)
UniProt
Find proteins for Q56310 (Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8)) Explore Q56310  Go to UniProtKB:  Q56310

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HG	C [auth A], D [auth B]	MERCURY (II) ION Hg BQPIGGFYSBELGY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 0.285 
• R-Value Work: 0.213 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 61.8	α = 90
b = 126.5	β = 95.6
c = 75.1	γ = 90

Software Package:

Software Name	Purpose
PHASES	phasing
MADPHSREF	model building
X-PLOR	refinement
DENZO	data reduction
SCALEPACK	data scaling
MADPHSREF	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1998-12-14 
• Released Date: 1999-12-15 
Deposition Author(s): Bilwes, A.M., Alex, L.A., Crane, B.R., Simon, M.I.

Revision History  

• Version 1.0: 1999-12-15
  Type: Initial release
  
• Version 1.1: 2007-10-16
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance