Striving to Recreate the Universal Origin of Life With His Own Hands 

My specialty is physical chemistry, and my goal is to create artificial life based on chemistry. For as long as I can remember, I have loved living things and creative projects. When I was in junior high school, I was already determined to create artificial life after learning about the “chemical evolution” hypothesis of the origin of life from a book. This has remained my goal ever since. 

According to the hypothesis of chemical evolution, small molecules gave rise to large molecules, which in turn gave rise to aggregates of those molecules, and then these aggregates suddenly acquired the ability to self-reproduce, giving rise to life on Earth as we know it today. The book discussed a type of molecular aggregate called coacervate droplets, which are believed to be the origin of life, but said nothing about how these droplets acquired the ability to self-reproduce. I was anxious to know the answer, and also determined to solve the mystery myself someday. 

Later, in a high school biology class, I learned that cells and the organelles inside them are almost entirely made up of phospholipid vesicles (liposomes). This made me wonder if it might be possible to create life by building a molecular system that enables phospholipid vesicles to grow and divide. Then, while reading the book Seimei Shisutemu wo Dou Rikai Suruka (Understanding Living Systems) by Makoto Asashima, I learned that a group at the University of Tokyo is studying this topic. Later, I was able to actually conduct research in that lab, starting with my undergraduate thesis, and went on to receive my doctorate. 

Recreating the emergence of the first life on Earth around 4 billion years ago 

In my past research, I applied physical chemistry knowledge and techniques to develop autocatalytic molecular aggregates, which take up nutrients and self-reproduce continuously, as well as self-oscillating molecular aggregates, which recursively oscillate on their own. This is because two characteristics of life are “taking in substances from the environment and proliferating” and “changing form and moving autonomously without any external forces or stimuli.” 

In the peptide-based molecular system I created, when the precursor substance, or nutrient, is added to water, it polymerizes and forms peptides, which are polymers of amino acids. Eventually, these peptides spontaneously aggregate to form microscopic liquid structures called droplets. Coacervate droplets, which are believed to have played an important role in the origin of life, are also droplets like these. In my research team’s experiments, we found that continuing to stimulate the droplets and give them nutrients caused them to divide and self-grow continuously. In other words, they self-reproduce as they metabolize nutrients. 

We also found that these self-reproduced droplets are able to concentrate nucleic acids such as RNA and DNA that are given to them, and droplets that take up nucleic acids are more likely to survive changes in the external environment. Organisms have a property called autopoeisis, which means that they can self-reproduce while maintaining their own system even in the face of a changing external environment. We are confident that this research is brings us closer to solving the mystery of the origin of life, or how primitive cells acquired autopoiesis billions of years ago. 

Seeking to create artificial life with inorganic self-reproducing materials 

My research project on “Discovery and Application of Autonomous Micropumps” was recently selected for the Japan Science and Technology Agency’s ACT-X program. The goal for this project is to expand on past research to create actual materials with real-world uses in manufacturing and other industries. As humans, we are able to execute recursive movements such as walking because our hearts are constantly beating. Recursion, like this beating of the heart, is essential for autonomous operation and manufacturing. The first thing we did for our ACT-X project was to achieve self-oscillation in organic droplets to create such molecular systems. In this molecular system, the droplets produce a driving substance through chemical reactions, which causes the droplets to oscillate and move around on their own. The droplets also use this driving substance as a signaling substance, allowing them to communicate with each other and move while self-organizing—that is, synchronized swimming. A paper summarizing these results is currently in review. 

The self-reproducing and self-oscillating molecular aggregates we developed were made entirely of organic materials, just like living things on Earth today. However, the industrial potential of these materials would be greater if a similar system were made from inorganic materials, which are more heat-resistant and chemically stable than organic materials. This is why we also proposed the creation of an automated micropump using an inorganic membrane with self-oscillation based on a system in which physical properties are recursively changed through chemical reactions for ACT-X. 

We have made considerable progress in the eight months from when we started the research in April 2024 to the end of 2024. The black, hemispherical object about 2 mm in diameter seen on the left side of the video is an autonomous micropump made of inorganic material that we are currently developing. This micropump autonomously self-organizes in water and functions like a pump, autonomously undergoing recursive cycles of osmosis and ejection to continuously produce sperm-shaped microstructures. We filed a patent application for this micropump in 2024 (Patent Application No. JP.2024-145899), and plan to request a patent examination and submit a paper by the end of 2025. 

More recently, we also discovered conditions that enable these sperm-shaped microstructures to swim autonomously. We hope to leverage our newly developed technology to create the world’s first self-actuated materials that manufacture their own self-actuated materials. Life on this planet has been autonomously navigating its environment for 3.8 billion years, taking in nutrients from its surroundings to continuously proliferate itself in an unbroken cycle. One of the defining features of life is that it recursively moves and creates itself. Prompt engineering, which is a technique used to make AI software create AI, has been attracting interest recently. If we are successful in our quest to develop materials that continue to create themselves and other things autonomously, we should be able to create truly life-like robots unlike anything in use today.