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Characterization of Bathyarchaeota genomes assembled from metagenomes of biofilms residing in mesophilic and thermophilic biogas reactors
2018, Maus, I., Rumming, M., Bergmann, I., Heeg, K., Pohl, M., Nettmann, E., Jaenicke, S., Blom, J., PĆ¼hler, A., SchlĆ¼ter, A., Sczyrba, A., Klocke, M.
Background: Previous studies on the Miscellaneous Crenarchaeota Group, recently assigned to the novel archaeal phylum Bathyarchaeota, reported on the dominance of these Archaea within the anaerobic carbohydrate cycle performed by the deep marine biosphere. For the first time, members of this phylum were identified also in mesophilic and thermophilic biogas-forming biofilms and characterized in detail. Results: Metagenome shotgun libraries of biofilm microbiomes were sequenced using the Illumina MiSeq system. Taxonomic classification revealed that between 0.1 and 2% of all classified sequences were assigned to Bathyarchaeota. Individual metagenome assemblies followed by genome binning resulted in the reconstruction of five metagenome-assembled genomes (MAGs) of Bathyarchaeota. MAGs were estimated to be 65-92% complete, ranging in their genome sizes from 1.1 to 2.0 Mb. Phylogenetic classification based on core gene sets confirmed their placement within the phylum Bathyarchaeota clustering as a separate group diverging from most of the recently known Bathyarchaeota clusters. The genetic repertoire of these MAGs indicated an energy metabolism based on carbohydrate and amino acid fermentation featuring the potential for extracellular hydrolysis of cellulose, cellobiose as well as proteins. In addition, corresponding transporter systems were identified. Furthermore, genes encoding enzymes for the utilization of carbon monoxide and/or carbon dioxide via the Wood-Ljungdahl pathway were detected. Conclusions: For the members of Bathyarchaeota detected in the biofilm microbiomes, a hydrolytic lifestyle is proposed. This is the first study indicating that Bathyarchaeota members contribute presumably to hydrolysis and subsequent fermentation of organic substrates within biotechnological biogas production processes.
Effect of a Profound Feedstock Change on the Structure and Performance of Biogas Microbiomes
2020, Klang, Johanna, Szewzyk, Ulrich, Bock, Daniel, Theuerl, Susanne
In this study the response of biogas-producing microbiomes to a profound feedstock change was investigated. The microbiomes were adapted to the digestion of either 100% sugar beet, maize silage, or of the silages with elevated amounts of total ammonium nitrogen (TAN) by adding ammonium carbonate or animal manure. The feedstock exchange resulted in a short-range decrease or increase in the biogas yields according to the level of chemical feedstock complexity. Fifteen taxa were found in all reactors and can be considered as generalists. Thirteen taxa were detected in the reactors operated with low TAN and six in the reactors with high TAN concentration. Taxa assigned to the phylum Bacteroidetes and to the order Spirochaetales increased with the exchange to sugar beet silage, indicating an affinity to easily degradable compounds. The recorded TAN-sensitive taxa (phylum Cloacimonetes) showed no specific affinity to maize or sugar beet silage. The archaeal community remained unchanged. The reported findings showed a smooth adaptation of the microbial communities, without a profound negative impact on the overall biogas production indicating that the two feedstocks, sugar beet and maize silage, potentially do not contain chemical compounds that are difficult to handle during anaerobic digestion.
Draft Genome Sequence of a New Oscillospiraceae Bacterium Isolated from Anaerobic Digestion of Biomass
2020, Pascual, Javier, Hahnke, Sarah, Abendroth, Christian, Langer, Thomas, Ramm, Patrice, Klocke, Michael, Luschnig, Olaf, Porcar, Manuel
Here, we present the genome sequence and annotation of the novel bacterial strain HV4-5-C5C, which may represent a new genus within the family Oscillospiraceae (order Eubacteriales). This strain is a potential keystone species in the hydrolysis of complex polymers during anaerobic digestion of biomass. Ā© 2020 Pascual et al.
Complete Genome Sequence of a New Ruminococcaceae Bacterium Isolated from Anaerobic Biomass Hydrolysis
2018, Hahnke, Sarah, Abendroth, Christian, Langer, Thomas, CodoƱer, Francisco M., Ramm, Patrice, Porcar, Manuel, Luschnig, Olaf, Klocke, Michael
A new Ruminococcaceae bacterium, strain HV4-5-B5C, participating in the anaerobic digestion of grass, was isolated from a mesophilic two-stage laboratoryscale leach bed biogas system. The draft annotated genome sequence presented in this study and 16S rRNA gene sequence analysis indicated the affiliation of HV4-5- B5C with the family Ruminococcaceae outside recently described genera. Ā© 2018 Hahnke et al.
Complete genome sequence of a new clostridium sp. isolated from anaerobic digestion and biomethanation
2020, Hahnke, Sarah, Abendroth, Christian, Pascual, Javier, Langer, Thomas, Ramm, Patrice, Klocke, Michael, Luschnig, Olaf, Porcar, Manuel
Here, we present the genome sequence and annotation of the bacterial strain HV4-5-A1G, a potentially new Clostridium species. Based on its genomic data, this strain may act as a keystone microorganism in the hydrolysis of complex polymers, as well as in the different acidogenesis and acetogenesis steps during anaerobic digestion. Ā© 2020 Hahnke et al.
Complete genome sequence of a new Bacteroidaceae bacterium isolated from anaerobic biomass digestion
2020, Hahnke, Sarah, Abendroth, Christian, Pascual, Javier, Langer, Thomas, CodoƱer, Francisco M., Ramm, Patrice, Klocke, Michael, Luschnig, Olaf, Porcare, Manuel
Here, we present the genome sequence and annotation of HV4-6-C5C, a bacterial strain isolated from a mesophilic two-stage laboratory-scale leach bed biogas reactor system. Strain HV4-6-C5C may represent a new genus of the family Bacteroidaceae and may have a key role in acidogenesis and acetogenesis steps during anaerobic biomass digestion. Ā© 2019 Hahnke et al.