The Potential of Artificial Cells Functioning under In Situ Deep-Sea Conditions.

Artificial cells with reconstructed cellular functions could serve as practical protocell models for studying the early cellular life on the Earth. Investigating the viability of protocell models in extreme environments where life may have arisen is important for advancing origin-of-life research. Here, we tested the survivability of lipid membrane vesicles in deep-sea environments. The vesicles were submerged in the deep-sea floor with a human-occupied vehicle. Although most of the vesicles were broken, some vesicles maintained a spherical shape after the dives. When a cell-free protein synthesis system was encapsulated inside, a few vesicles remained even after a 1,390 m depth dive. Interestingly, such artificial cells could subsequently synthesize protein in a nutrient-rich buffer solution. Together with on shore experiments showing artificial cells synthesized protein under high pressure, our results suggest artificial cells may be able to express genes in deep-sea environments where thermal energy is available from hydrothermal vents.