Free-Living, Heterotrophic Protists – Exploring Genomic and Metabolic Capabilities (ProMeta).

• Applicant: Dr. Kenneth Dumack
• Subject Area: Systematics and Morphology (Zoology) ; Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 536829148

Reference genomes of prokaryotes have been immensely useful in exploring their metabolic capabilities and ecological functioning. However, reference genomes of non-fungal microeukaryotes (protists) are scarce, resulting in poor understanding of protistan functions. Eukaryotic genomes are complex and large, making their exploration challenging with current sequencing technologies. Even more problematic are contaminations by prokaryotes, which cannot be avoided when attempting to sequence the genomes of bacteria predators. Consequently, the majority of existing protistan genomes are from parasites or algae, and freeliving, heterotrophic protists remain neglected. The recent discovery of Saccharomycomorpha psychra provides a unique opportunity to explore a genome of a free-living, heterotrophic protist. S. psychra belongs to the eukaryotic infrakingdom Rhizaria, a taxon with a similar diversity as plants, and is a species of the class Sarcomonadea. The highly diverse Sarcomonadea likely represent the most abundant predators of terrestrial bacteria. Unlike most other Sarcomonadea species, S. psychra does not feed on bacteria but grows similar to yeast, making it possible to be cultured without environmental bacteria. This represents a unique possibility to sequence a Sarcomonadea genome and explore its metabolic capabilities. Our goal is to sequence the first high-quality genome of a free-living, heterotrophic Rhizaria (WP1), determine and quantify which genes are upregulated under distinct food sources (WP2), and explore the yet uncharted diversity of this exciting taxon by further isolating, barcoding, and describing new strains (WP3).

• DFG Programme: Research Grants
• Co-Investigator: Dr. Kwee Boon Brandon Seah