Alternative Architecture of the <i>E. coli</i> Chemosensory Array

• Main Authors: Alister Burt, C. Keith Cassidy, Phillip J. Stansfeld, Irina Gutsche
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Biomolecules
• Subjects: chemosensory array; chemotaxis; <i>E. coli</i>; cryo-electron tomography; molecular modelling
• Online Access: https://www.mdpi.com/2218-273X/11/4/495

Chemotactic responses in motile bacteria are the result of sophisticated signal transduction by large, highly organized arrays of sensory proteins. Despite tremendous progress in the understanding of chemosensory array structure and function, a structural basis for the heightened sensitivity of networked chemoreceptors is not yet complete. Here, we present cryo-electron tomography visualisations of native-state chemosensory arrays in <i>E. coli</i> minicells. Strikingly, these arrays appear to exhibit a p2-symmetric array architecture that differs markedly from the p6-symmetric architecture previously described in <i>E. coli</i>. Based on this data, we propose molecular models of this alternative architecture and the canonical p6-symmetric assembly. We evaluate our observations and each model in the context of previously published data, assessing the functional implications of an alternative architecture and effects for future studies.