9JQO

Polyrod formed by FlgG (G65V) from the Salmonella TH26292 strain

This is a non-PDB format compatible entry.

Summary for 9JQO

• Entry DOI: 10.2210/pdb9jqo/pdb
• EMDB information: 61731 80383
• Descriptor: Flagellar basal-body rod protein FlgG (1 entity in total)
• Functional Keywords: flagella motor. polyrod, p ring on polyrod complex, cryo-em, spa, salmonella, motor protein
• Biological source: Salmonella enterica subsp. enterica serovar Typhimurium
• Total number of polymer chains: 48
• Total formula weight: 1335690.58

Authors

Yamaguchi, T.,Kato, T.,Minamino, T.,Namba, K. (deposition date: 2024-09-27, release date: 2026-02-04, Last modification date: 2026-07-29)

Primary citation

Yamaguchi, T.,Minamino, T.,Kato, T.,Chevance, F.F.V.,Hughes, K.T.,Namba, K.
Structural insights into the assembly mechanism of the molecular bushing in the bacterial flagellar motor.
Commun Biol, 2026

PubMed Abstract: The LP-ring complex of the Salmonella flagellar motor acts as a bushing that supports high-speed rotation of the rod, which serves as a drive shaft. The L-ring, P-ring, and distal rod consist of FlgH, FlgI, and FlgG, respectively. LP-ring formation begins with P-ring assembly around the distal rod, where it remains firmly attached until the L-ring assembles above it. L-ring formation induces P-ring detachment, allowing the rod to freely rotate within the LP-ring, but this mechanism remains unclear. Here, we report the cryoEM structure of the P-ring assembled on a polyrod, an unusually elongated rod structure. The P-ring exhibits a slightly elliptical shape with a 2.7° tilt relative to the rod axis for its stable attachment. However, L-ring assembly on the P-ring causes steric clashes with the rod to induce P-ring detachment, allowing it to adopt a circular shape and complete the LP-ring as a functional bushing.

PubMed: 42443432
DOI: 10.1038/s42003-026-10640-y

Experimental method

ELECTRON MICROSCOPY (3.37 Å)