Asymmetric localization of the cell division machinery during Bacillus subtilis sporulation
- University of California, San Diego, United States
Abstract
The Gram-positive bacterium Bacillus subtilis can divide via two modes. During vegetative growth, the division septum is formed at the midcell to produce two equal daughter cells. However, during sporulation, the division septum is formed closer to one pole to yield a smaller forespore and a larger mother cell. Using cryo-electron tomography, genetics and fluorescence microscopy, we found that the organization of the division machinery is different in the two septa. While FtsAZ filaments, the major orchestrators of bacterial cell division, are present uniformly around the leading edge of the invaginating vegetative septa, they are only present on the mother cell side of the invaginating sporulation septa. We provide evidence suggesting that the different distribution and number of FtsAZ filaments impact septal thickness, causing vegetative septa to be thicker than sporulation septa already during constriction. Finally, we show that a sporulation-specific protein, SpoIIE, regulates asymmetric divisome localization and septal thickness during sporulation.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Additionally, we have deposited representative tomograms for each growth condition in the Electron Microscopy Data Bank (EMDB) accession codes EMD-23963, EMD-23964, EMD-23965, EMD-23966, EMD-23967 and EMD-23968, and tilt series in the Electron Microscopy Public Image Archive (EMPIAR) database accession code EMPIAR-10710.
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Tomogram of a dividing vegetative cell of Bacillus subtilisElectron Microscopy Data Bank ID EMD-20335.
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Tomogram of a dividing vegetative cell of Bacillus subtilisElectron Microscopy Data Bank ID EMD-20335.
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Tomogram of a dividing vegetative cell of Bacillus subtilis FtsZ-linker(Q-rich) strainElectron Microscopy Data Bank ID EMD-20335.
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Tomogram of a dividing sporulating cell of Bacillus subtilisElectron Microscopy Data Bank ID EMD-20335.
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Tomogram of a dividing sporulating cell of Bacillus subtilisElectron Microscopy Data Bank ID EMD-20335.
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Tomogram of a dividing sporulating cell of Bacillus subtilis SpoIIE null mutantElectron Microscopy Data Bank ID EMD-20335.
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Tilt series of dividing vegetative and sporulating cells of Bacillus subtilisElectron Microscopy Public Image Archive ID EMPIAR-10710.
Article and author information
Author details
Funding
National Institutes of Health (R01-GM057045)
- Kit Pogliano
- Elizabeth Villa
National Science Foundation (DBI 1920374)
- Elizabeth Villa
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication. We acknowledge the use of San Diego Nanotechnology Infrastructure (SDNI) of UC San Diego, a member of the National Nanotechnology Coordinated Infrastructure, supported by the NSF grant ECCS-1542148. Please note it was not possible to add this to the above above Funders tab as it was not awarded to an author.
Copyright
© 2021, Khanna 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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Asymmetric localization of the cell division machinery during Bacillus subtilis sporulation
eLife 10:e62204.
https://doi.org/10.7554/eLife.62204
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