Biological Assembly 1  

 3D View: Structure | Electron Density

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

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

Macromolecule Content

• Total Structure Weight: 48.27 kDa 
• Atom Count: 4019 
• Modelled Residue Count: 425 
• Deposited Residue Count: 426 
• Unique protein chains: 1

3G67

Crystal Structure of a Soluble Chemoreceptor from Thermotoga maritima

• DOI: 10.2210/pdb3G67/pdb

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


• Deposited: 2009-02-06 Released: 2009-07-28 
• Deposition Author(s): Pollard, A.M., Bilwes, A.M., Crane, B.R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.17 Å
• R-Value Free: 0.278 
• R-Value Work: 0.242 

Literature

The structure of a soluble chemoreceptor suggests a mechanism for propagating conformational signals.

Pollard, A.M., Bilwes, A.M., Crane, B.R.

(2009) Biochemistry 48: 1936-1944

• PubMed: 19149470 
• DOI: 10.1021/bi801727m
• Primary Citation of Related Structures:  
  3G67, 3G6B


• PubMed Abstract: 
  

Transmembrane chemoreceptors, also known as methyl-accepting chemotaxis proteins (MCPs), translate extracellular signals into intracellular responses in the bacterial chemotaxis system. MCP ligand binding domains control the activity of the CheA kinase, situated approximately 200 A away, across the cytoplasmic membrane. The 2.17 A resolution crystal structure of a Thermotoga maritima soluble receptor (Tm14) reveals distortions in its dimeric four-helix bundle that provide insight into the conformational states available to MCPs for propagating signals. A bulge in one helix generates asymmetry between subunits that displaces the kinase-interacting tip, which resides more than 100 A away. The maximum bundle distortion maps to the adaptation region of transmembrane MCPs where reversible methylation of acidic residues tunes receptor activity. Minor alterations in coiled-coil packing geometry translate the bulge distortion to a >25 A movement of the tip relative to the bundle stalks. The Tm14 structure discloses how alterations in local helical structure, which could be induced by changes in methylation state and/or by conformational signals from membrane proximal regions, can reposition a remote domain that interacts with the CheA kinase.

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Organizational Affiliation: 

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

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Methyl-accepting chemotaxis protein	A, B	213	Thermotoga maritima	Mutation(s): 0  Gene Names: Tm0014, TM_0014
UniProt
Find proteins for Q7DFA3 (Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8)) Explore Q7DFA3  Go to UniProtKB:  Q7DFA3

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.17 Å
• R-Value Free: 0.278 
• R-Value Work: 0.242 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 68.712	α = 90
b = 25.747	β = 93.81
c = 119.61	γ = 90

Software Package:

Software Name	Purpose
ADSC	data collection
SOLVE	phasing
CNS	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2009-02-06 
• Released Date: 2009-07-28 
Deposition Author(s): Pollard, A.M., Bilwes, A.M., Crane, B.R.

Revision History  

• Version 1.0: 2009-07-28
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance