Origin of Life: Hypothesis Traces First Protocells Back to Emergence of Cell Membrane Bioenergetics

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A coherent pathway — which starts from no more than rocks, water and carbon dioxide and leads to the emergence of the strange bio-energetic properties of living cells — has been traced for the first time in a major hypothesis paper in Cell this week.


At the origin of life the first protocells must have needed a vast amount of energy to drive their metabolism and replication, as enzymes that catalyse very specific reactions were yet to evolve. Most energy flux must have simply dissipated without use.

So where did it all that energy come from on the early Earth, and how did it get focused into driving the organic chemistry required for life?

The answer lies in the chemistry of deep-sea hydrothermal vents. In their paper Nick Lane (UCL, Genetics, Evolution and Environment) and Bill Martin (University of Dusseldorf) address the question of where all this energy came from — and why all life as we know it conserves energy in the peculiar form of ion gradients across membranes.

“Life is, in effect, a side-reaction of an energy-harnessing reaction. Living organisms require vast amounts of energy to go on living,” said Nick Lane.

Written By: Science Daily
continue to source article at sciencedaily.com

4 COMMENTS

  1. Does this indicate that organic molecules (or even a living ‘protocell’)  might be created experimentally by mimicking conditions in found in deep-sea hydrothermal vents? 

    (my ignorance is unlimited!)

  2. Nodhimmi
    Does this indicate that organic molecules (or even a living ‘protocell’)  might be created experimentally by mimicking conditions in found in deep-sea hydrothermal vents? 

    I think it would be very difficult to copy the conditions of these temperatures and pressures in a lab!
    Organic molecules however, seem to be found everywhere:-  from nebulae in deep-space, to various bodies in the Solar System and on Earth.

    http://www.ceoe.udel.edu/deeps… –
    The first hydrothermal vent was discovered in 1977. They are known to exist in the Pacific and Atlantic oceans. Most are found at an average depth of about 2,100 meters (7,000 ft) in areas of seafloor spreading along the Mid-Ocean Ridge system- the underwater mountain chain that snakes its way around the globe.

    How do hydrothermal vents form? In some areas along the Mid-Ocean Ridge, the gigantic plates that form the Earth’s crust are moving apart, creating cracks and crevices in the ocean floor. 

    Seawater seeps into these openings and is heated by the molten rock, or magma, that lies beneath the Earth’s crust. As the water is heated, it rises and seeks a path back out into the ocean through an opening in the seafloor.

    As the vent water bursts out into the ocean, its temperature may be as high as 400°C (750°F). Yet this water does not boil because it is under so much pressure from the tremendous weight of the ocean above. When the pressure on a liquid is increased, its boiling point goes up.

    Chimneys top some hydrothermal vents. These smokestacks are formed from dissolved metals that precipitate out (form into particles) when the super-hot vent water meets the surrounding deep ocean water, which is only a few degrees above freezing.

    So-called “black smokers” are the hottest of the vents. They spew mostly iron and sulfide, which combine to form iron monosulfide. This compound gives the smoker its black color.
    “White smokers” release water that is cooler than their cousins’ and often contains compounds of barium, calcium, and silicon, which are white.

    They do seem to provide chemical food for various organisms living far from the sunlight which powers surface ecosystems.

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