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Title: Bacterial flagellar capping proteins adopt diverse oligomeric states

Abstract

Flagella are crucial for bacterial motility and pathogenesis. The flagellar capping protein (FliD) regulates filament assembly by chaperoning and sorting flagellin (FliC) proteins after they traverse the hollow filament and exit the growing flagellum tip. In the absence of FliD, flagella are not formed, resulting in impaired motility and infectivity. Here, we report the 2.2 Å resolution X-ray crystal structure of FliD fromPseudomonas aeruginosa, the first high-resolution structure of any FliD protein from any bacterium. Using this evidence in combination with a multitude of biophysical and functional analyses, we find thatPseudomonasFliD exhibits unexpected structural similarity to other flagellar proteins at the domain level, adopts a unique hexameric oligomeric state, and depends on flexible determinants for oligomerization. Considering that the flagellin filaments on which FliD oligomers are affixed vary in protofilament number between bacteria, our results suggest that FliD oligomer stoichiometries vary across bacteria to complement their filament assemblies.

Authors:
ORCiD logo; ; ; ; ; ; ; ; ; ORCiD logo; ; ; ORCiD logo
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Institutes of Health (NIH)
OSTI Identifier:
1357646
Resource Type:
Journal Article
Resource Relation:
Journal Name: eLife; Journal Volume: 5; Journal Issue: 9
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Postel, Sandra, Deredge, Daniel, Bonsor, Daniel A., Yu, Xiong, Diederichs, Kay, Helmsing, Saskia, Vromen, Aviv, Friedler, Assaf, Hust, Michael, Egelman, Edward H., Beckett, Dorothy, Wintrode, Patrick L., and Sundberg, Eric J. Bacterial flagellar capping proteins adopt diverse oligomeric states. United States: N. p., 2016. Web. doi:10.7554/eLife.18857.
Postel, Sandra, Deredge, Daniel, Bonsor, Daniel A., Yu, Xiong, Diederichs, Kay, Helmsing, Saskia, Vromen, Aviv, Friedler, Assaf, Hust, Michael, Egelman, Edward H., Beckett, Dorothy, Wintrode, Patrick L., & Sundberg, Eric J. Bacterial flagellar capping proteins adopt diverse oligomeric states. United States. doi:10.7554/eLife.18857.
Postel, Sandra, Deredge, Daniel, Bonsor, Daniel A., Yu, Xiong, Diederichs, Kay, Helmsing, Saskia, Vromen, Aviv, Friedler, Assaf, Hust, Michael, Egelman, Edward H., Beckett, Dorothy, Wintrode, Patrick L., and Sundberg, Eric J. 2016. "Bacterial flagellar capping proteins adopt diverse oligomeric states". United States. doi:10.7554/eLife.18857.
@article{osti_1357646,
title = {Bacterial flagellar capping proteins adopt diverse oligomeric states},
author = {Postel, Sandra and Deredge, Daniel and Bonsor, Daniel A. and Yu, Xiong and Diederichs, Kay and Helmsing, Saskia and Vromen, Aviv and Friedler, Assaf and Hust, Michael and Egelman, Edward H. and Beckett, Dorothy and Wintrode, Patrick L. and Sundberg, Eric J.},
abstractNote = {Flagella are crucial for bacterial motility and pathogenesis. The flagellar capping protein (FliD) regulates filament assembly by chaperoning and sorting flagellin (FliC) proteins after they traverse the hollow filament and exit the growing flagellum tip. In the absence of FliD, flagella are not formed, resulting in impaired motility and infectivity. Here, we report the 2.2 Å resolution X-ray crystal structure of FliD fromPseudomonas aeruginosa, the first high-resolution structure of any FliD protein from any bacterium. Using this evidence in combination with a multitude of biophysical and functional analyses, we find thatPseudomonasFliD exhibits unexpected structural similarity to other flagellar proteins at the domain level, adopts a unique hexameric oligomeric state, and depends on flexible determinants for oligomerization. Considering that the flagellin filaments on which FliD oligomers are affixed vary in protofilament number between bacteria, our results suggest that FliD oligomer stoichiometries vary across bacteria to complement their filament assemblies.},
doi = {10.7554/eLife.18857},
journal = {eLife},
number = 9,
volume = 5,
place = {United States},
year = 2016,
month = 9
}
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