Download MendeleyNative flagellar MS ring is formed by 34 subunits with 23-fold and 11-fold subsymmetries.
Kawamoto, A., Miyata, T., Makino, F., Kinoshita, M., Minamino, T., Imada, K., Kato, T., Namba, K.(2021) Nat Commun 12: 4223-4223
- PubMed: 34244518
- DOI: https://doi.org/10.1038/s41467-021-24507-9
- Primary Citation of Related Structures:
7D84 - PubMed Abstract:
The bacterial flagellar MS ring is a transmembrane complex acting as the core of the flagellar motor and template for flagellar assembly. The C ring attached to the MS ring is involved in torque generation and rotation switch, and a large symmetry mismatch between these two rings has been a long puzzle, especially with respect to their role in motor function. Here, using cryoEM structural analysis of the flagellar basal body and the MS ring formed by full-length FliF from Salmonella enterica, we show that the native MS ring is formed by 34 FliF subunits with no symmetry variation. Symmetry analysis of the C ring shows a variation with a peak at 34-fold, suggesting flexibility in C ring assembly. Finally, our data also indicate that FliF subunits assume two different conformations, contributing differentially to the inner and middle parts of the M ring and thus resulting in 23- and 11-fold subsymmetries in the inner and middle M ring, respectively. The internal core of the M ring, formed by 23 subunits, forms a hole of the right size to accommodate the protein export gate.
Organizational Affiliation:
Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan.
