Structure and dynamics of the E. coli chemotaxis core signaling complex by cryo-electron tomography and molecular simulations

DOI: 10.1038/s42003-019-0748-0

Authors: C. Keith Cassidy (University of Oxford; University of Illinois at Urbana-Champaign) , Benjamin A. Himes (University of Pittsburgh School of Medicine) , Dapeng Sun (University of Pittsburgh School of Medicine) , Jun Ma (University of Pittsburgh School of Medicine) , Gongpu Zhao (University of Pittsburgh School of Medicine) , John S. Parkinson (University of Utah) , Phillip J. Stansfeld (University of Oxford; University of Warwick) , Zaida Luthey-Schulten (University of Illinois at Urbana-Champaign) , Peijun Zhang (University of Pittsburgh School of Medicine; Wellcome Trust Centre for Human Genetics, University of Oxford; , Diamond Light Source)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Communications Biology , VOL 3

State: Published (Approved)
Published: December 2020

Abstract: To enable the processing of chemical gradients, chemotactic bacteria possess large arrays of transmembrane chemoreceptors, the histidine kinase CheA, and the adaptor protein CheW, organized as coupled core-signaling units (CSU). Despite decades of study, important questions surrounding the molecular mechanisms of sensory signal transduction remain unresolved, owing especially to the lack of a high-resolution CSU structure. Here, we use cryo-electron tomography and sub-tomogram averaging to determine a structure of the Escherichia coli CSU at sub-nanometer resolution. Based on our experimental data, we use molecular simulations to construct an atomistic model of the CSU, enabling a detailed characterization of CheA conformational dynamics in its native structural context. We identify multiple, distinct conformations of the critical P4 domain as well as asymmetries in the localization of the P3 bundle, offering several novel insights into the CheA signaling mechanism.

Journal Keywords: Computational models; Cryoelectron tomography

Diamond Keywords: Bacteria

Subject Areas: Biology and Bio-materials, Chemistry


Technical Areas:

Added On: 07/01/2021 09:53

Documents:
s42003-019-0748-0.pdf

Discipline Tags:

Biochemistry Chemistry Structural biology Life Sciences & Biotech

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