Download MendeleyCryo-EM analysis of the SctV cytosolic domain from the enteropathogenic E. coli T3SS injectisome.
Majewski, D.D., Lyons, B.J.E., Atkinson, C.E., Strynadka, N.C.J.(2020) J Struct Biol 212: 107660-107660
- PubMed: 33129970
- DOI: https://doi.org/10.1016/j.jsb.2020.107660
- Primary Citation of Related Structures:
7K08 - PubMed Abstract:
The bacterial injectisome and flagella both rely on type III secretion systems for their assembly. The syringe-like injectisome creates a continuous channel between the bacterium and the host cell, through which signal-modulating effector proteins are secreted. The inner membrane pore protein SctV controls the hierarchy of substrate selection and may also be involved in energizing secretion. We present the 4.7 Å cryo-EM structure of the SctV cytosolic domain (SctV C ) from the enteropathogenic Escherichia coli injectisome. SctV C forms a nonameric ring with primarily electrostatic interactions between its subunits. Molecular dynamics simulations show that monomeric SctV C maintains a closed conformation, in contrast with previous studies on flagellar homologue FlhA. Comparison with substrate-bound homologues suggest that a conformational change would be required to accommodate binding partners.
Organizational Affiliation:
Department of Biochemistry and Molecular Biology and the Center for Blood Research, University of British Columbia, Vancouver, British Columbia, Canada.
