Welcome to the Todd Group Research Overview! We are broadly interested in prebiotic chemistry, the origins of life, and planetary habitability. In particular, we aim to constrain a plausible and continuous path for the origins of life, from the chemical feedstocks readily available on planets, to the synthesis of prebiotic precursors of life in planetary environments, and finally to the first self-evolving system (perhaps protocells) under realistic planetary conditions. Our work is highly interdisciplinary, making use of fields such as astronomy, planetary science, geology, chemistry, biochemistry, physics, etc.
Theme 1 – Chemical environments available on planets
We are interested in understanding what types of chemicals are available in various planetary environments. Sources of organic and volatile molecules on planets include impacts, atmospheric photochemistry, lightning generation, redox surface chemistry, volcanism, etc. Understanding what molecules are available, what concentrations they are present in, and how long they last are some of our goals. This work involves a combination of theory and experiments.
Theme 2 – Prebiotic synthesis in planetary environments
Once we know what chemical constituents are present in the environment, we’d like to constrain how prebiotic chemistry could plausibly lead to the synthesis of precursors of life. By precursors, we could mean molecules like amino acids, ribonucleotides, sugars, and lipids – or we could mean something else. It’s unknown if life must use the same biomolecules we find on Earth, or if alternative chemistries are possible. We like to be fairly agnostic on this question, and keep an open mind for possible alternative types of life. We like to constrain how the synthesis of precursors occurs under realistic planetary environments.
Theme 3 – Protocells – one possibility for the first life
If a prebiotic soup containing biomolecular precursors is available on a planet, we’re still not there yet. That’s to say, this isn’t yet alive. What is the first living system? We don’t really know, but one option is a protocell. Perhaps a protocell formed spontaneously from a lipid membrane contains some genetic information, metabolites, or primitive ability to perform catalysis. If such a system can begin replicating and evolving, perhaps this could be a living system. Our work studies how protocells could carry out the functions thought to be necessary for the first life forms in plausible planetary environments.
