Functional reconstitution of a bacterial CO2 concentrating mechanism in E. coli
- University of California, Berkeley, United States
- Weizmann Institute of Science, Israel
- University of California, San Diego, United States
- ETH Zurich, Switzerland
- Max Planck Institute of Molecular Plant Physiology, Germany
Abstract
Many photosynthetic organisms employ a CO2 concentrating mechanism (CCM) to increase the rate of CO2 fixation via the Calvin cycle. CCMs catalyze ≈50% of global photosynthesis, yet it remains unclear which genes and proteins are required to produce this complex adaptation. We describe the construction of a functional CCM in a non-native host, achieved by expressing genes from an autotrophic bacterium in an E. coli strain engineered to depend on rubisco carboxylation for growth. Expression of 20 CCM genes enabled E. coli to grow by fixing CO2 from ambient air into biomass, with growth in ambient air depending on the components of the CCM. Bacterial CCMs are therefore genetically compact and readily transplanted, rationalizing their presence in diverse bacteria. Reconstitution enabled genetic experiments refining our understanding of the CCM, thereby laying the groundwork for deeper study and engineering of the cell biology supporting CO2 assimilation in diverse organisms.
Data availability
All source data for all figures is available in the linked github repository along with accompanying Jupyter notebooks generating the data-driven portions of all figures.
Article and author information
Author details
Sumedha Ravishankar
Funding
Energy Biosciences Institute (CW163755)
- David Savage
US Department of Energy (DE-SC00016240)
- David Savage
European Research Council (NOVCARBFIX 646827)
- Ron Milo
National Science Foundation (MCB-1818377)
- David Savage
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Flamholz 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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Functional reconstitution of a bacterial CO2 concentrating mechanism in E. coli
eLife 9:e59882.
https://doi.org/10.7554/eLife.59882
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