Origin of Life


Prebiotic Life in the Solar System

Is there a link between organic molecules on comets and in the deep ocean?   Were the organic molecules and water on comets the seeds for life on earth? ROVs collect data in the deep oceans and deep space to answer these questions.  

Search for the origins of life on earth and its occurrence elsewhere in the universe continues to be a challenging question. The early earth was only populated with simple non-living inorganic and organic chemical compounds, and yet after several billions of years, is currently inhabited by diverse forms of cellular life that range widely in complexity. Based on the working principle that life originated in pre-biotic chemistry, we are exploring the prebiotic chemistry that could lead to the emergence of existing biogeochemical pathways and cellular life on earth.

 

Transition Metal based Autocatalytic Cycles

All existing cellular life on earth is essentially characterized by metabolism that is composed of cascades of enzyme-catalyzed biochemical reactions assembled into networks. Some of these biochemical networks are autocatalytic cycles that are central to all metabolic pathways. Thus, to understand the emergence of life, we need to understand the emergence of such cycles in the landscape of prebiotic chemistry, that is without protein based enzymes as catalysts. To accomplish such a goal, we are experimentally investigating proto-metabolic chemical reactions and look for conditions that would enable self-organization of the compounds into chemical networks. Transition metals are the central components of early earth minerals, and have powerful catalytic abilities. Our work aims at reconstructing representative autocatalytic metabolic cycles using transition metals as enzyme-surrogates to effect catalytic transformations of cycle compounds. This would provide insights into the processes involved in the self-organization of a chemical system and its emergence as a metabolic network. Furthermore, it may reveal the production of novel compounds that may serve as additional signature diagnostic tools in our search for extra-terrestrial life.

 

Exploring the Outer Solar Systems

Numerous spacecraft are exploring the solar system looking at conditions and processes that existed at the formation of the solar system that may give us clues to the development of life on earth.  These include the exploration of planets, comets, and asteroids. 

Missions Exploring the Solar System….

 

Subsurface Oceans in the Solar System

Water is the key to carbon based life as we know it. Earth is the only planet or moon that has a permanent surface oceans, although Mars may have had oceans in the geologic past and recent observation suggest that there is still some flowing water on the surface.  However, it is becoming apparent that there are many extraterrestrial bodies that have deep subsurface oceans.  In fact, there is more water in these moons and planetoids than hundreds of earth’s oceans.  

Do these oceans support abiogenic synthesis of organic compounds?  Do planets need to be in the “Goldilocks” zone to support life or do we have a “Surface Chauvinism” that has limited our conceptualization of the origin of life.   With the recognition that there is massive amounts of subsurface water in the solar system, we are seeing a paradigm shift in our understanding of the abiogenic origin of organic molecules.

Europa, one of Jupiter’s moons, may have a subsurface ocean sandwiched between an icy shell and a volcanic core.  These conditions maybe conducive to the biogenic synthesis of complex organics,  Life under Europa.