3JA6

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

Summary for 3JA6

• Entry DOI: 10.2210/pdb3ja6/pdb
• EMDB information: 6319 6320
• Descriptor: Chemotaxis protein CheW, Chemotaxis protein CheA, Methyl-accepting chemotaxis protein 2, ... (4 entities in total)
• Functional Keywords: bacterial chemotaxis, core-signaling unit, adaptor protein, histidine kinase, chemoreceptor, signaling protein
• Biological source: Escherichia coli; More
• Total number of polymer chains: 18
• Total formula weight: 547598.46

Authors

Cassidy, C.K.,Himes, B.A.,Alvarez, F.J.,Ma, J.,Zhao, G.,Perilla, J.R.,Schulten, K.,Zhang, P. (deposition date: 2015-04-21, release date: 2015-12-09, Last modification date: 2024-02-21)

Primary citation

Cassidy, C.K.,Himes, B.A.,Alvarez, F.J.,Ma, J.,Zhao, G.,Perilla, J.R.,Schulten, K.,Zhang, P.
CryoEM and computer simulations reveal a novel kinase conformational switch in bacterial chemotaxis signaling.
Elife, 4:e08419-e08419, 2015

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.

PubMed: 26583751
DOI: 10.7554/eLife.08419

Experimental method

ELECTRON MICROSCOPY (12.7 Å)