Autotrophy at the thermodynamic limit of life: a model for energy conservation in acetogenic bacteria.

Nat Rev Microbiol

Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.

Published: December 2014

Life on earth evolved in the absence of oxygen with inorganic gases as potential sources of carbon and energy. Among the alternative mechanisms for carbon dioxide (CO₂) fixation in the living world, only the reduction of CO₂ by the Wood-Ljungdahl pathway, which is used by acetogenic bacteria, complies with the two requirements to sustain life: conservation of energy and production of biomass. However, how energy is conserved in acetogenic bacteria has been an enigma since their discovery. In this Review, we discuss the latest progress on the biochemistry and genetics of the energy metabolism of model acetogens, elucidating how these bacteria couple CO₂ fixation to energy conservation.

Download full-text PDF

Source
http://dx.doi.org/10.1038/nrmicro3365DOI Listing

Publication Analysis

Top Keywords

acetogenic bacteria
12
energy conservation
8
co₂ fixation
8
energy
6
autotrophy thermodynamic
4
thermodynamic limit
4
limit life
4
life model
4
model energy
4
conservation acetogenic
4

Similar Publications

Acetogenic bacteria play an important role in various biotechnological processes, because of their chemolithoautotrophic metabolism converting carbon dioxide with molecular hydrogen (H) as electron donor into acetate. As the main factor limiting acetogenesis is often H, insights into the H consumption kinetics of acetogens are required to assess their potential in biotechnological processes. In this study, initial H consumption rates at a range of different initial H concentrations were measured for three different acetogens.

View Article and Find Full Text PDF

Peatlands are invaluable but threatened ecosystems that store huge amounts of organic carbon globally and emit the greenhouse gasses carbon dioxide (CO) and methane (CH). Trophic interactions of microbial groups essential for methanogenesis are poorly understood in such systems, despite their importance. Thus, the present study aimed at unraveling trophic interactions between fermenters and methanogens in a nitrogen-limited, subarctic, pH-neutral fen.

View Article and Find Full Text PDF

Corrinoids are cobalt-containing tetrapyrroles. They include adenosylcobalamin (vitamin B) and cobamides that function as cofactors and coenzymes for methyl transfer, radical-dependent and redox reactions. Though cobamides are the most complex cofactors in nature, they are essential in the acetyl-CoA pathway, thought to be the most ancient CO-fixation pathway, where they perform a pterin-to-cobalt-to-nickel methyl transfer reaction catalyzed by the corrinoid iron-sulphur protein (CoFeS).

View Article and Find Full Text PDF
Article Synopsis
  • * Researchers used metagenomic and cultivation-based methods to analyze the microbiomes and found stable microbial communities similar to those from critical early Earth periods, indicating a link between present-day microbes and historical biospheric evolution.
  • * The Upper Jurassic aquifer, rich in CO and influenced by magmatic processes, hosts a unique ecosystem that may reflect early Earth conditions, contributing valuable insights into microbial evolution and the formation of the modern biosphere.
View Article and Find Full Text PDF

Advanced aspects of acetogens.

Bioresour Technol

December 2024

Institute of Molecular Biology and Biotechnology of Prokaryotes, University of Ulm, Ulm, Germany. Electronic address:

Acetogens are a diverse group of anaerobic bacteria that are capable of carbon dioxide fixation and have for long fascinated scientists due to their unique metabolic prowess. Historically, acetogens have been recognized for their remarkable ability to grow and to produce acetate from different one-carbon sources, including carbon dioxide, carbon monoxide, formate, methanol, and methylated organic compounds. The key metabolic pathway in acetogens responsible for converting these one-carbon sources is ́the Wood-Ljungdahl pathway.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!