Length-dependent flagellar growth of Vibrio alginolyticus revealed by real time fluorescent imaging

  1. Meiting Chen
  2. Ziyi Zhao
  3. Jin Yang
  4. Kai Peng
  5. Matthew A.B. Baker
  6. Fan Bai  Is a corresponding author
  7. Chien-Jung Lo  Is a corresponding author
  1. National Central University, Taiwan, Republic of China
  2. Peking University, China
  3. University of New South Wales, Australia

Abstract

Bacterial flagella are extracellular filaments that drive swimming in bacteria. During its assembly, flagellins are transported unfolded through the central channel in the flagellum to the growing tip. Here we applied in vivo fluorescent imaging to monitor in real time the Vibrio alginolyticus polar flagella growth. The flagellar growth rate is found to be highly length-dependent. Initially, the flagellum grows at a constant rate (50nm/min) when shorter than 1500nm. The growth rate decays sharply when the flagellum grows longer. We modeled flagellin transport inside the channel as a one-dimensional diffusive process with an injection force at its base. When the flagellum is short, its growth rate is determined by the loading speed at the base. Only when the flagellum grows longer does diffusion of flagellin become the rate-limiting step, dramatically reducing the growth rate. Our results shed new light on the dynamic building process of this complex extracellular structure.

Article and author information

Author details

  1. Meiting Chen

    Physics, National Central University, Jhongli, Taiwan, Republic of China
    Competing interests
    The authors declare that no competing interests exist.
  2. Ziyi Zhao

    Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Jin Yang

    Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  4. Kai Peng

    Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, China
    Competing interests
    The authors declare that no competing interests exist.
  5. Matthew A.B. Baker

    EMBL Australia Node for Single Molecule Science, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  6. Fan Bai

    Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, China
    For correspondence
    fbai@pku.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
  7. Chien-Jung Lo

    Phyiscs, National Central University, Jhongli, Taiwan, Republic of China
    For correspondence
    cjlo@phy.ncu.edu.tw
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8078-4970

Funding

Ministry of Science and Technology, Taiwan (MOST-103-2112-M-008-010-MY3)

  • Chien-Jung Lo

National Natural Science Foundation of China (No. 31370847,No.31327901)

  • Fan Bai

Human Frontier Science Program (RGP0041/2015)

  • Fan Bai
  • Chien-Jung Lo

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Richard M Berry, University of Oxford, United Kingdom

Publication history

  1. Received: October 7, 2016
  2. Accepted: January 15, 2017
  3. Accepted Manuscript published: January 18, 2017 (version 1)
  4. Accepted Manuscript updated: January 19, 2017 (version 2)
  5. Version of Record published: February 9, 2017 (version 3)

Copyright

© 2017, Chen et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Meiting Chen
  2. Ziyi Zhao
  3. Jin Yang
  4. Kai Peng
  5. Matthew A.B. Baker
  6. Fan Bai
  7. Chien-Jung Lo
(2017)
Length-dependent flagellar growth of Vibrio alginolyticus revealed by real time fluorescent imaging
eLife 6:e22140.
https://doi.org/10.7554/eLife.22140
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