Biological Assembly 1  

 3D View: Structure

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Hetero 18-mer - A12B4C2 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 547.60 kDa 
• Atom Count: 38314 
• Modelled Residue Count: 5010 
• Deposited Residue Count: 5010 
• Unique protein chains: 4

3JA6

Cryo-electron Tomography and All-atom Molecular Dynamics Simulations Reveal a Novel Kinase Conformational Switch in Bacterial Chemotaxis Signaling

• DOI: 10.2210/pdb3JA6/pdb
• EMDataResource: EMD-6319

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


• Deposited: 2015-04-21 Released: 2015-12-09 
• Deposition Author(s): Cassidy, C.K., Himes, B.A., Alvarez, F.J., Ma, J., Zhao, G., Perilla, J.R., Schulten, K., Zhang, P.

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 12.7 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: TOMOGRAPHY 

Literature

CryoEM and computer simulations reveal a novel kinase conformational switch in bacterial chemotaxis signaling.

Cassidy, C.K., Himes, B.A., Alvarez, F.J., Ma, J., Zhao, G., Perilla, J.R., Schulten, K., Zhang, P.

(2015) Elife 4: e08419-e08419

• PubMed: 26583751 
• DOI: 10.7554/eLife.08419
• Primary Citation of Related Structures:  
  3JA6


• PubMed Abstract: 
  

Chemotactic responses in bacteria require large, highly ordered arrays of sensory proteins to mediate the signal transduction that ultimately controls cell motility. A mechanistic understanding of the molecular events underlying signaling, however, has been hampered by the lack of a high-resolution structural description of the extended array. Here, we report a novel reconstitution of the array, involving the receptor signaling domain, histidine kinase CheA, and adaptor protein CheW, as well as a density map of the core-signaling unit at 11.3 Å resolution, obtained by cryo-electron tomography and sub-tomogram averaging. Extracting key structural constraints from our density map, we computationally construct and refine an atomic model of the core array structure, exposing novel interfaces between the component proteins. Using all-atom molecular dynamics simulations, we further reveal a distinctive conformational change in CheA. Mutagenesis and chemical cross-linking experiments confirm the importance of the conformational dynamics of CheA for chemotactic function.

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Organizational Affiliation: 

Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Chemotaxis protein CheW	A, B, D, F	139	Escherichia coli	Mutation(s): 0
Find proteins for Q56311 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)) Explore Q56311  Go to UniProtKB:  Q56311

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Chemotaxis protein CheA	C, E	379	Escherichia coli	Mutation(s): 0  EC: 2.7.13.3
Find proteins for Q56310 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)) Explore Q56310  Go to UniProtKB:  Q56310

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Methyl-accepting chemotaxis protein 2	G, I, K, M, O, Q	309	Escherichia coli	Mutation(s): 0
Find proteins for Q9X0M7 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)) Explore Q9X0M7  Go to UniProtKB:  Q9X0M7

Entity ID: 4
Molecule	Chains	Sequence Length	Organism	Details	Image
Methyl-accepting chemotaxis protein 2	H, J, L, N, P, R	307	Escherichia coli	Mutation(s): 0
Find proteins for Q9X0M7 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)) Explore Q9X0M7  Go to UniProtKB:  Q9X0M7

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 12.7 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: TOMOGRAPHY 

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2015-04-21 
• Released Date: 2015-12-09 
Deposition Author(s): Cassidy, C.K., Himes, B.A., Alvarez, F.J., Ma, J., Zhao, G., Perilla, J.R., Schulten, K., Zhang, P.

Revision History  

• Version 1.0: 2015-12-09
  Type: Initial release