Related Experiment Video
Updated: Apr 13, 2026

Electron Cryotomography of Bacterial Cells
Published on: May 6, 2010
Complete atomic model of the bacterial flagellar filament by electron cryomicroscopy
Koji Yonekura1, Saori Maki-Yonekura, Keiichi Namba
1Protonic NanoMachine Project, ERATO, JST.
Abstract:
The bacterial flagellar filament is a helical propeller for bacterial locomotion. It is a helical assembly of a single protein, flagellin, and its tubular structure is formed by 11 protofilaments in two distinct conformations, L- and R-type, for supercoiling. The X-ray crystal structure of a flagellin fragment lacking about 100 terminal residues revealed the protofilament structure, but the full filament structure is still essential for understanding the mechanism of supercoiling and polymerization. Here we report a complete atomic model of the R-type filament by electron cryomicroscopy. A density map obtained from image data up to 4 A resolution shows the feature of alpha-helical backbone and some large side chains. The atomic model built on the map reveals intricate molecular packing and an alpha-helical coiled coil formed by the terminal chains in the inner core of the filament, with its intersubunit hydrophobic interactions having an important role in stabilizing the filament.
More Related Videos
11:33Using Tomoauto: A Protocol for High-throughput Automated Cryo-electron Tomography
Published on: January 30, 2016
09:12Applying Live Cell Imaging and Cryo-Electron Tomography to Resolve Spatiotemporal Features of the Legionella pneumophila Dot/Icm Secretion System
Published on: March 10, 2020
Related Concept Videos
Cytoskeletal Proteins in Bacteria
Studying the Cytoskeleton
Formation of Intermediate Filaments
Cryo-electron Microscopy
Special Staining Techniques
Flagella and Motility in Bacteria