Crash landing of Vibrio cholerae by MSHA pili-assisted braking and anchoring in a viscoelastic environment
Abstract
Mannose-sensitive hemagglutinin (MSHA) pili and flagellum are critical for the surface attachment of Vibrio cholerae, the first step of V. cholerae colonization on host surfaces. However, the cell landing mechanism remains largely unknown, particularly in viscoelastic environments such as the mucus layers of intestines. Here, combining the cysteine-substitution-based labelling method with single-cell tracking techniques, we quantitatively characterized the landing of V. cholerae by directly observing both pili and flagellum of cells in a viscoelastic non-Newtonian solution consisting of 2% Luria-Bertani and 1% methylcellulose (LB+MC). The results show that MSHA pili are evenly distributed along the cell length and can stick to surfaces at any point along the filament. With such properties, MSHA pili are observed to act as a brake and anchor during cell landing which include three phases: running, lingering, and attaching. Importantly, loss of MSHA pili results in a more dramatic increase in mean path length in LB+MC than in 2% LB only or in 20% Ficoll solutions, indicating that the role of MSHA pili during cell landing is more apparent in viscoelastic non-Newtonian fluids than viscous Newtonian ones. Our work provides a detailed picture of the landing dynamics of V. cholerae under viscoelastic conditions, which can provide insights into ways to better control V. cholerae infections in real mucus-like environment.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1-6.
Article and author information
Author details
Funding
National Key R and D Program of China (2018YFA0902102)
- Kun Zhao
National Natural Science Foundation of China (31770132)
- Zhi Liu
National Natural Science Foundation of China (81572050)
- Zhi Liu
National Natural Science Foundation of China (21621004)
- Kun Zhao
University of Bristol (Vice-Chancellor's Fellowship)
- Rachel R Bennett
Grant in aid for Young Scientists (17K15410)
- Andrew S Utada
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mice received the humane care and the experimental protocols were carried out in accordance with the Guide for the Care and Use of Laboratory Animals, Huazhong University of Science and Technology, as approved by the Animal Care Committee of Hubei Province.
Reviewing Editor
- Raymond E Goldstein, University of Cambridge, United Kingdom
Publication history
- Received: July 2, 2020
- Accepted: July 1, 2021
- Accepted Manuscript published: July 2, 2021 (version 1)
- Version of Record published: July 15, 2021 (version 2)
Copyright
© 2021, Zhang 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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