9WX3

Structure of flagellar hook subunit FlgE D-II domain in Pseudomonas aeruginosa

Summary for 9WX3

• Entry DOI: 10.2210/pdb9wx3/pdb
• Descriptor: Flagellar hook protein FlgE (2 entities in total)
• Functional Keywords: bacteria, pseudomonas aeruginosa, flagellar hook, universal joint, motor protein
• Biological source: Pseudomonas aeruginosa PAO1
• Total number of polymer chains: 2
• Total formula weight: 41326.76

Authors

Lu, G.,You, Y. (deposition date: 2025-09-24, release date: 2025-12-24)

Primary citation

You, Y.,Lin, S.,Yang, F.,Chen, Z.,Ye, F.,Guo, Y.,He, B.,Cao, Y.,Gu, J.,Lu, G.
Structural characterization of Pseudomonas aeruginosa flagellar hook FlgE reveals a novel beta-hairpin element involved in inflammatory modulation.
Int.J.Biol.Macromol., 332:148466-148466, 2025

PubMed Abstract: The flagellar hook subunit FlgE of Pseudomonas aeruginosa (Pa-FlgE) is a core component of the bacterial surface flagellum. It is also identified as an important virulence factor capable of modulating host inflammatory response. Herein, we report the high-resolution crystal structures of Pa-FlgE domain I (D-I) and domain II (D-II), both of which adopt predominantly β-structure. Structural comparison among Pa-FlgE and its orthologs shows that D-I and the core-barrel of D-II are highly conserved. Two peripheral insertions of variable length and structure, however, are identified in FlgE D-II. In Pa-FlgE, these two insertions fold as a loop element and a β-hairpin element, respectively. Notably, these two elements are solvent-exposed and extend towards one another, and deletion of the two elements either simultaneously or individually is shown to abolish the immunomodulation activity of Pa-FlgE. While the loop element is present in other FlgE orthologs, the β-hairpin is unique to Pa-FlgE, suggesting that P. aeruginosa has evolved this distinctive β-hairpin in flagellar hook to modulate the inflammatory response during infection.

PubMed: 41130485
DOI: 10.1016/j.ijbiomac.2025.148466

Experimental method

X-RAY DIFFRACTION (1.8 Å)