Length-dependent flagellar growth of Vibrio alginolyticus revealed by real time fluorescent imaging
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
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
- Richard M Berry, University of Oxford, United Kingdom
Version history
- Received: October 7, 2016
- Accepted: January 15, 2017
- Accepted Manuscript published: January 18, 2017 (version 1)
- Accepted Manuscript updated: January 19, 2017 (version 2)
- 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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