Microorganisms isolated from Australian subterranean termite (Nasutitermes exitiosus) for biogenic hydrogen production.. Clostrida for biogenic hydrogen production

Biogenically produced hydrogen has the potential to be a global energy source that is relatively environmentally safe and produced at low cost using waste streams as feedstocks. Biogenic hydrogen is produced as an endproduct of fermentation, and is normally co-produced with a form of reduced carbon, typically CO2. Termites naturally host a range of prokaryotes that facilitate lignocelluloses digestion in the gut, including a range of taxa that are known to produce hydrogen. In the present study, a highly hydrogenogenic enrichment culture from the gut of worker caste Australian subterranean termites (Nasutitermes exitiosus) was developed and shown to convert xylan to commercially significant quantities of hydrogen with relatively little CO2. The hydrogenogenic culture was comprised, almost exclusively, of three clostridial taxa which were named Ne1, Ne2 and Ne3 after N. exitiosus. Contigs belonging to these three genomes were separated from the metagenome and checked manually. Ne1 was a strain of Clostridium beijerinckii, Ne2 was a novel taxon related to Clostridium magnum while Ne3 was a Ruminiclostridium species.