Periodic Reporting for period 3 - SYMBIOSES (Novel Symbioses)
Période du rapport: 2024-01-01 au 2025-06-30
Endosymbioses represent mergers of two cells and generate new combinations of biochemical capabilities. Such innovations can promote rapid diversification by driving the new entity into previously inaccessible ecological niches. They have profoundly impacted the evolution of life and continue to shape the ecology of countless species. The project aims to establish an "engineering-via-endosymbioses approach" to introduce novel features into model eukaryotes and contribute to our understanding of the emergence of stable endosymbiotic outcomes.
Through this project, we developed an approach that uses Fluid Force Microscopy (FluidFM) to manipulate organelles within living cells and initiate novel endosymbiosis by direct bacterial implantation into novel host cells. This technology combines atomic force microscopy, optical microscopy, and nanofluidics. As a proof of concept, we transplanted organelles, here mitochondria, from cell to cell. These fused with the organelles of the host cells and replicated their genetic material over generations, enabling the study of the organelles' behavior and fate over extended periods. Building on this technological advance, we inject different bacterial strains into the cytoplasm of host cells to observe endosymbiotic interactions in real-time. The model bacterium Escherichia coli exhibited robust growth within host cells, posing a challenge for establishing a stable symbiotic relationship. To address this, we introduced specific nutrient deficiencies to slow down bacterial growth, resulting in a more balanced symbiotic relationship.
A particularly promising perspective of our approach is that endosymbioses can be followed from their initiation and the evolutionary trajectory can be studied over time. Exploring why and how symbioses work and why they go extinct is of pivotal interest, but likewise, understanding under which conditions parasitism takes over is important to study. Ultimately, such research has the potential to lead to new strategies to prevent detrimental parasitic behavior of intracellular pathogens. In addition, it may allow the establishment of novel beneficial symbioses for biotechnological applications.