Jerlström-Hultqvist lab

Symbioses between eukaryotes and prokaryotes have been crucial to major evolutionary transitions and have contributed to increased biodiversity. These partnerships have led to the development of specialized functions and organs in various multicellular organisms, such as nitrogen-fixing legumes, insects, deep-sea vent organisms, and light organs in aquatic animals. Bacterial and archaeal symbioses also occur in many unicellular protists. However, the foundations of symbiosis in protists, the extent of integration between host and symbiont, and the adaptations of host cells remain largely unexplored. The research groups aims to understand how these collaborations work and how they have evolved.

Popular science presentation

Our research aims to understand how new organelles form. We focus on an amoeba, Anaeramoeba, which has recently been isolated from oxygen-poor marine sediments. Anaeramoeba has a symbiotic relationship with a sulfate-reducing bacterium that lives close to the amoeba's hydrogenosome. The bacteria reside within the amoeba in a tubular network of narrow channels that connect them to the cell's exterior. Through these channels, the bacteria can absorb sulfate from seawater, even though they live inside the amoeba. How the membrane organelle that maintains this complex connection between Anaeramoeba and the bacteria has developed and been maintained over time is still unknown.

We use modern methods to investigate the symbiosis from multiple perspectives. With the latest sequencing technologies, we map the complete genome sequences of both the amoeba and its symbionts, allowing for in-depth studies of their evolutionary relationships. The close interaction between the amoeba and the symbiont is analyzed using fluorescence microscopy and high-resolution tomographic electron microscopy techniques.

Screenshot UU news 2024-03-18
Screenshot UU news 2024-03-18

Research

Collaborations between unrelated cells through symbiosis are widespread in nature. In most symbiotic relationships, cells exchange nutrients in a process known as syntrophy. Symbiosis has been studied for over a century and is fundamental to many processes essential for life. A notable example is the partnership between plants and nitrogen-fixing bacteria, which enables certain plants to thrive in nitrogen-deficient environments. Plants develop specialized structures, called symbiosomes, that facilitate interaction with these bacteria and reward them for their role.

While most studies on symbiotic organelles have focused on multicellular organisms, there is much less research on similar symbioses found in single-celled eukaryotes (protists) in oxygen-poor environments. Our research group explores the mechanisms that drive these symbioses and their evolutionary origins. We aim to uncover how new organelles emerge and the processes that regulate them.

Alumni

Oscar Åberg, former Master student

Ka Hei Lam, former Master student

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