Inspenet, September 15, 2023.
The European research project Micro4Biogas, led by Manuel Porcar from the University of Valencia, has identified and characterized a new group of bacteria specialized in the decomposition of organic matter, which could have a positive impact on the production of biogas .
80 samples of decomposing organic matter were collected from 45 large-scale biogas production plants located in Germany, the Netherlands and Austria. These were subjected to DNA sequencing to analyze their microbial composition.
The newly identified set of bacteria, called Darwinibacteriales, represents one of the most common populations in reactors used to produce biogas. Although they had never been thoroughly investigated before, they turned out to be present in all 80 samples analyzed, despite the variations and diverse geographical location of the biogas production plants.
Improving biogas production could have a significant impact on the energy industry by reducing dependence on fossil fuels and energy imports. However, the lack of research in microbiology has been an obstacle to the advancement of this sector.
Porcar noted that his research “reveals a small part of a vast set of microorganisms that probably play a fundamental role in biogas production, but that have never before been analyzed at the genomic level.”
Research that breaks new ground
This finding paves the way for the next step, which is to develop highly efficient and optimized communities of biogas-producing microorganisms . This would allow biogas production plants to operate more robustly and require fewer subsidies to compete in the market, which in turn would boost the use of renewable energy globally.
To understand the composition and variety of microbial communities present in all collected samples, taxonomic analysis was carried out by sequencing a specific gene, the 16S rRNA gene, in all samples.
In previous studies, MBA03 had been identified as a group of bacteria that had not been grown in laboratory environments, although significant attention had not been paid to it, as explained by Adriel Latorre, the study’s lead author and director of the Department of Genomics in Darwin Bioprospecting.
To carry out a more exhaustive analysis of this previously unknown set of bacteria, we proceeded to complete sequencing of 30 samples in which the significant presence of MBA03 had been verified.
“But surprisingly, when we analyzed the complete metagenomes of the 30 samples, we did not detect MBA03 in any of them. This revealed a technical limitation: the genome of this taxon was not available in databases. From that moment on, our objective was clear: we had to isolate the MBA03 genome and describe it in depth,” stated Latorre.
Scientists hypothesize that Darwinibacteriaceae may be involved in a mutually cooperative relationship with archaea, another group of microorganisms that play a role in the anaerobic digestion process. Bacteria generate metabolic compounds that archaea use to produce methane gas . If this relationship is verified, these bacteria will become the main focus for the development of strategies aimed at increasing and improving biogas production.
The Micro4Biogas project brings together fifteen institutions from six countries, including universities, companies and the local government of a Spanish city where a state-of-the-art biogas plant will be built. Its main objective is to improve performance, speed, quality and reproducibility in biogas production. This will allow renewable energy to be consolidated as an environmentally, politically and economically viable option.