Insight into the evolution of microbial metabolism from the deep-branching bacterium, Thermovibrio ammonificans
- Rutgers University, United States
- Woods Hole Oceanographic Institution, United States
- DVGW-Technologiezentrum Wasser, Germany
- Ernst-Moritz-Arndt-University Greifswald, Germany
Abstract
Anaerobic thermophiles inhabit relic environments that resemble the early Earth. However, the lineage of these modern organisms co-evolved with our planet. Hence, these organisms carry both ancestral and acquired genes and serve as models to reconstruct early metabolism. Based on comparative genomic and proteomic analyses, we identified two distinct groups of genes in Thermovibrio ammonificans: the first codes for enzymes that do not require oxygen and use substrates of geothermal origin; the second appears to be a more recent acquisition, and may reflect adaptations to cope with the rise of oxygen on Earth. We propose that the ancestor of the Aquificae was originally a hydrogen oxidizing, sulfur reducing bacterium that used a hybrid carbon fixation pathway for CO2 fixation. With the gradual rise of oxygen in the atmosphere, more efficient terminal electron acceptors became available and this lineage acquired genes that increased its metabolic flexibility while retaining ancestral metabolic traits.
Data availability
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Thermovibrio ammonificans complete genome sequencePublicly available at the NCBI Genome (accession no: NC_014926.1).
Article and author information
Author details
Costantino Vetriani
Funding
National Science Foundation (MCB 04-56676)
- Costantino Vetriani
National Aeronautics and Space Administration (NNX15AM18G)
- Costantino Vetriani
National Science Foundation (OCE 03-27353)
- Costantino Vetriani
National Science Foundation (MCB 08-43678)
- Costantino Vetriani
National Science Foundation (OCE 09-37371)
- Costantino Vetriani
National Science Foundation (OCE 11-24141)
- Costantino Vetriani
National Science Foundation (MCB 15-17567)
- Donato Giovannelli
- Costantino Vetriani
National Science Foundation (OCE-1136727)
- Stefan M Sievert
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Giovannelli 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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Insight into the evolution of microbial metabolism from the deep-branching bacterium, Thermovibrio ammonificans
eLife 6:e18990.
https://doi.org/10.7554/eLife.18990
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