Three-dimensional biofilm colony growth supports a mutualism involving matrix and nutrient sharing
- Stanford University, United States
- University of Michigan, United States
- University of Wisconsin, United States
- University of California, San Francisco, United States
Abstract
Life in a three-dimensional biofilm is typical for many bacteria, yet little is known about how strains interact in this context. Here, we created essential-gene CRISPRi knockdown libraries in biofilm-forming Bacillus subtilis and measured competitive fitness during colony co-culture with wild type. Partial knockdown of some translation-related genes reduced growth rates and led to out-competition. Media composition led some knockdowns to compete differentially as biofilm versus non-biofilm colonies. Cells depleted for the alanine racemase AlrA died in monoculture but survived in a biofilm-colony co-culture via nutrient sharing. Rescue was enhanced in biofilm-colony co-culture with a matrix-deficient parent, due to a mutualism involving nutrient and matrix sharing. We identified several examples of mutualism involving matrix sharing that occurred in three-dimensional biofilm colonies but not when cultured in two dimensions. Thus, growth in a three-dimensional colony can promote genetic diversity through sharing of secreted factors and may drive evolution of mutualistic behavior.
Data availability
Related scripts and data deposited in Dryad Digital Repository (doi:10.5061/dryad.79cnp5htm). Remaining data generated or analysed during this study is included in the manuscript and supporting files.
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Three-dimensional biofilm growth supports a mutualism involving matrix and nutrient sharing - related scripts and dataDryad Digital Repository, 10.5061/dryad.79cnp5htm.
Article and author information
Author details
Kerwyn Casey Huang
Funding
Paul G. Allen Foundation (Discovery Center at Stanford on Systems Modeling of Infection)
- Heidi A Arjes
- Kerwyn Casey Huang
National Institutes of Health (K22 Award AI137122)
- Jason Peters
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Arjes 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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Three-dimensional biofilm colony growth supports a mutualism involving matrix and nutrient sharing
eLife 10:e64145.
https://doi.org/10.7554/eLife.64145
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