Nanoscale resolution of microbial fiber degradation in action
- University of Zurich, Switzerland
- Ben-Gurion University of the Negev, Israel
- National Renewable Energy Laboratory, United States
- Weizmann Institute of Science, Israel
- University of Zürich, Switzerland
Abstract
The lives of microbes unfold at the micron scale, and their molecular machineries operate at the nanoscale. Their study at these resolutions is key towards achieving a better understanding of their ecology. We focus on cellulose degradation of the canonical Clostridium thermocellum system to comprehend how microbes build and use their cellulosomal machinery at these nanometer scales. Degradation of cellulose, the most abundant organic polymer on Earth, is instrumental to the global carbon cycle. We reveal that bacterial cells form 'cellulosome capsules' driven by catalytic product-dependent dynamics, which can increase the rate of hydrolysis. Biosynthesis of this energetically costly machinery and cell growth are decoupled at the single-cell level, hinting at a division-of-labor strategy through phenotypic heterogeneity. This novel observation highlights intra-population interactions as key to understanding rates of fiber degradation.
Data availability
Structural data that support the findings of this study has been deposited in the Electron Microscopy Data Bank https://www.ebi.ac.uk/emdb/ (accession code EMD-11986). Representative data set can be found in EMPIAR under the accession number EMPIAR-10593.
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Cryo-EM structure of exoglucanase Cel48SElectron Microscopy Data Bank, EMD-11986.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (2476/2 -1)
- Ohad Medalia
- Itzhak Mizrahi
HORIZON EUROPE European Research Council (64084)
- Itzhak Mizrahi
Swiss national foundation (31003A_179418)
- Ohad Medalia
Center for Bioenergy Innovation
- Yannick J Bomble
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Nanoscale resolution of microbial fiber degradation in action
eLife 11:e76523.
https://doi.org/10.7554/eLife.76523
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