ORIGINS - Organic molecular generation of protocells on iron minerals

Lead Research Organisation: Newcastle University
Department Name: Sch of Natural & Environmental Sciences


How life originated on our planet is one of the great unsolved scientific questions. While no rocks survive from this early in Earth's history, clues can be gained from scraps of evidence from biological 'fossils' still present in microorganisms today, a consideration of what early Earth environments were probably like, and by looking at similar environments on the modern Earth. Together the evidence is consistent with an origin of life at warm to hot (< 150 deg C) alkaline hydrothermal vents ('hot springs'), where iron-rich minerals helped react hydrogen gas from the hydrothermal vents and carbon dioxide from the oceans or surface water into the organic 'building blocks' of life. One problem, however, is that experiments trying to mimic this chemistry under relevant conditions have only formed very short organic molecules of 3 carbon atoms in length or less. These are too short to build the larger organic 'building blocks' of life; most importantly cell membranes essential for separating the cell (the basic unit of life) from outside water to allow the control of chemical gradients and later evolution of internal biochemistry.

In ORIGINS we will build on exciting new experimental results from a pilot study at Newcastle University where we have formed long chains of organic molecules (including the building blocks of cell membranes) on iron-minerals under conditions mimicking the mixing of alkaline hydrothermal vent fluid with water at < 100 deg C. We will determine how different iron-minerals and water chemistries can form the key organic building blocks of early life. We will then aim to show how these organic building blocks can, given the right conditions, lift off the minerals and self-assemble into 'protocells'; membrane-bounded organic spheres with a strong resemblance to modern microbial cells; a key stepping-stone to life. Finally, we will take the first steps to test if these protocells can use metal-mineral clusters embedded within them to generate further organic molecules, grow, and replicate.

ORIGINS will have impact on both Earth and beyond. Research will be linked to an outreach program in the NE of England, using interactive workshops to inspire school age children to continue with science-based subjects. ORIGINS will also aid the search for life elsewhere in our solar system. Icy moons such as Jupiter's moon Europa and Saturn's moon Enceladus are thought to have similar alkaline hydrothermal vents at the bottom of their deep ice-covered oceans, and samples of them brought up by hydrothermal plumes to the moons' surfaces or expelled into space. We will link into the recently launched European Space Agency JUICE (Jupiter Icy Moons Explorer) mission, recently started on its eight year journey to explore Jupiter's icy moons. Samples of the organic molecules and protocells made in ORIGINS experiments will be used to test the ability of identical instruments to those on the JUICE spacecraft to detect organic molecules on the moons' surfaces prior to its arrival.


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