The Syntrophic Hydrogen Economy: Metabolic Adaptations and Bioenergy Potential of Anaerobic Microbial Eukaryotes

Time period:

1 July 2025 – 30 June 2028

Project leader:

Princess R. Cabotaje

Funder:

Swedish Research Council

Type of award:

Grant for positions or stipends

Total funding:

4,050,000 SEK

Resource sharing among organisms sustains life, even in low-oxygen environments. Here, single-celled eukaryotes (protists) and prokaryotes (bacteria) share electrons often via hydrogen (H2) exchange—a process termed “syntrophy”. Despite their large global presence and ecological importance, protists, such as ´breviates,´ remain understudied. Knowledge gaps persist regarding how environmental factors, molecular mechanisms, and H2-handling enzymes (i.e., hydrogenases) influence these syntrophic partnerships. This project investigates the environmental factors, metabolic strategies, symbiosis infrastructure, and role of hydrogenases in breviates and their prokaryotic partners. How temperature, oxygen, and electron acceptors influence syntrophy will be resolved through controlled-exposure experiments. High-resolution imaging, mass spectrometry, and spatial omics will map cellular biomolecules revealing adaptations enabling these interactions. The role and regulation of hydrogenases in syntrophy efficiency and stability will be clarified via H2 uptake/evolution assays and identifying cofactor preferences. This 3-year project leverages expertise at the Okinawa Institute of Science and Technology (24 months) and Uppsala University (12 months). The expected outcomes include a deeper understanding of microbial syntrophy, their roles in evolution and ecosystems, improving predictions of ecosystem responses to environmental change, and potential bio-inspired clean energy technologies.