There is a research arm of the University of Illinois (Champaign-Urbana) called the Institute of Genomic Biology (IGB). This group has developed a theory for how life developed on the planet Earth. And this theory is clever because it offends no facts.
An affiliate of the IGB, Elbert Branscomb, put it this way: "Of course, one of the most powerful ways to address this question, and a worthy goal in its own right, is to try to understand how life came to be on this planet. The answer should help us discover what is truly necessary to spark the fateful transition from the lifeless to the living, and thereby, under what conditions and with what likelihood it might happen elsewhere."
More than 25 years ago, Michael Russell, a research scientist at the NASA Jet Propulsion Laboratory, came up with a potentially testable theory for the origin of life from inanimate matter. Recently he has published a further development of his theory with Wolfgang Nitschke (of the National Center for Scientific Research in Marseille, France) and Branscomb (the scientist quoted above).
Russell’s approach hypothesizes that inanimate chemicals transformed to living matter because of a geochemical process called serpentinization, a process that occurred on and just beneath the floor of Earth’s oceans approximately four billion years ago.
Here’s what the the Institute of Genomic Biology at the University of Illinois has to say about this process of serpentinization:
"One attractive aspect of the Russell hypothesis is that it provides potential explanations for several seemingly arbitrary and puzzling aspects of how all life on Earth works, including, most notably, how it taps into and exploits sources of energy. This process, quite oddly, involves constantly filling up and depleting a kind of chemical reservoir that is created by pushing a lot more protons onto one side of a membrane than the other—just like pumping water uphill to fill a lake behind a dam.
‘Then, mimicking how hydroelectric turbines are driven by water flowing downhill, these protons are only allowed to flow back "downhill" through the membrane by passing through a turbine-like molecular "generator," which creates, instead of high-voltage electricity, a chemical fuel called ATP, the cell's "gasoline." All cells then "burn" ATP in order to power their vital processes. The cells of air-breathing organisms, like us, "burn" ATP by ultimately converting oxygen to CO2.
"Furthermore, while every bacterial cell has its own proton reservoir system, our bigger cells contain and cultivate herds of "ex-bacteria" (called mitochondria) that maintain their own reservoir, ATP-producing turbines, etc.—a trick of "agricultural domestication" at the cellular level that makes it not only possible for multi-cellular organisms to exist but to be huge, fast, and dangerous.
"This "reservoir-mediated energy business" is not a minor undertaking of life, Branscomb notes. Every day our bodies produce and consume their weight in ATP molecules. In seconds, each newly made ATP molecule is used. In minutes, the body’s entire ATP energy reserve is consumed and regenerated."That’s why you can’t stand to be without oxygen for more than a few minutes," Branscomb said. "We live on a thin, desperate edge to keep our metabolic motors running full blast. Yet in spite of this desperation, the process isn’t carried out by using our energy sources directly, but by using the indirect, proton reservoir method. It’s an arrestingly strange way of doing business that has made many scientists question why it is this way."The amazing answer, Russell's model suggests, is because that's how life got launched. "Before there was anything lifelike to take advantage of it, the geochemical process of serpentinization produced "for free" (along with much else of critical importance) two of the major components of this energy system: cell-like compartments surrounded by membranes and proton concentration differences on each side of the membranes," Russell said."
"It's only later when life set out to take its act on the road that it had to figure out how to make its own membranes, pump protons uphill across these new membranes, tap into other sources of energy to do the pumping, etc.," Branscomb said. "But once hooked on the free stuff, the trans-membrane proton gradient in particular, life never broke the habit. And here we are, every living thing, still frantically pumping protons as if just staying alive depends on it—which it does."
Also notably, the Russell serpentinization hypothesis is founded directly on modern understandings regarding the physical nature of early Earth. In particular, at the time life arose, the world was almost entirely covered in a great, deep, and weakly-acidic ocean, the atmosphere was relatively oxidized and rich in CO2, and tectonic processes constantly replenished and destroyed the crusts of the ocean floor, as they still do today. And it is the exposure of newly made ocean crust to the ocean that gives rise to the geochemical magic of serpentinization.
"It is at least highly suggestive that every living thing is constantly and indeed furiously recreating something equivalent to this ancient ‘ocean effluent’ membrane-based proton gradient that serpentinization handed life to start with on the rocky floor of the ancient Hadean ocean," Branscomb said. "It was, in part, by exploiting that naturally-given, geochemical proton gradient that the engines required to produce the molecular ‘starter kit’ of life got going. So suddenly it’s obvious why we pump protons and use this silly method—we became dependent on this ‘free lunch’ energy system when life was born, developed a lot of fancy machinery for using it, and have never severed that umbilicus since."
"After Russell proposed this theory, scientists discovered a real-world example of an alkaline hot spring in the North Atlantic Ocean, famously called the Lost City. This geochemical edifice provides strong and detailed evidence in its structure and chemical properties for Russell’s model that origin-of-life expert Nick Lane, a senior lecturer at University College London, has called the only credible theory to date.
"One of the most important, and exciting, aspects of Russell’s hypothesis is that the key ideas can, in principle, be tested. This just-released paper and its companion paper by Nitschke and Russell in PTRSL-B have advanced Russell’s hypothesis and brought it substantially closer to experimental testing. To this end, Russell and his collaborators are currently making experimental model systems that recreate the serpentinization process, including the theory’s mineralogical membranes and chemical gradients."
Quotes and indented text were summarized from this link:
http://www.igb.illinois.edu/content/cracking-how-life-arose-earth-may-help-clarify-where-else-it-might-existAn affiliate of the IGB, Elbert Branscomb, put it this way: "Of course, one of the most powerful ways to address this question, and a worthy goal in its own right, is to try to understand how life came to be on this planet. The answer should help us discover what is truly necessary to spark the fateful transition from the lifeless to the living, and thereby, under what conditions and with what likelihood it might happen elsewhere."
More than 25 years ago, Michael Russell, a research scientist at the NASA Jet Propulsion Laboratory, came up with a potentially testable theory for the origin of life from inanimate matter. Recently he has published a further development of his theory with Wolfgang Nitschke (of the National Center for Scientific Research in Marseille, France) and Branscomb (the scientist quoted above).
Russell’s approach hypothesizes that inanimate chemicals transformed to living matter because of a geochemical process called serpentinization, a process that occurred on and just beneath the floor of Earth’s oceans approximately four billion years ago.
Here’s what the the Institute of Genomic Biology at the University of Illinois has to say about this process of serpentinization:
‘Then, mimicking how hydroelectric turbines are driven by water flowing downhill, these protons are only allowed to flow back "downhill" through the membrane by passing through a turbine-like molecular "generator," which creates, instead of high-voltage electricity, a chemical fuel called ATP, the cell's "gasoline." All cells then "burn" ATP in order to power their vital processes. The cells of air-breathing organisms, like us, "burn" ATP by ultimately converting oxygen to CO2.
"Furthermore, while every bacterial cell has its own proton reservoir system, our bigger cells contain and cultivate herds of "ex-bacteria" (called mitochondria) that maintain their own reservoir, ATP-producing turbines, etc.—a trick of "agricultural domestication" at the cellular level that makes it not only possible for multi-cellular organisms to exist but to be huge, fast, and dangerous.
"It's only later when life set out to take its act on the road that it had to figure out how to make its own membranes, pump protons uphill across these new membranes, tap into other sources of energy to do the pumping, etc.," Branscomb said. "But once hooked on the free stuff, the trans-membrane proton gradient in particular, life never broke the habit. And here we are, every living thing, still frantically pumping protons as if just staying alive depends on it—which it does."
Also notably, the Russell serpentinization hypothesis is founded directly on modern understandings regarding the physical nature of early Earth. In particular, at the time life arose, the world was almost entirely covered in a great, deep, and weakly-acidic ocean, the atmosphere was relatively oxidized and rich in CO2, and tectonic processes constantly replenished and destroyed the crusts of the ocean floor, as they still do today. And it is the exposure of newly made ocean crust to the ocean that gives rise to the geochemical magic of serpentinization.
"After Russell proposed this theory, scientists discovered a real-world example of an alkaline hot spring in the North Atlantic Ocean, famously called the Lost City. This geochemical edifice provides strong and detailed evidence in its structure and chemical properties for Russell’s model that origin-of-life expert Nick Lane, a senior lecturer at University College London, has called the only credible theory to date.
"One of the most important, and exciting, aspects of Russell’s hypothesis is that the key ideas can, in principle, be tested. This just-released paper and its companion paper by Nitschke and Russell in PTRSL-B have advanced Russell’s hypothesis and brought it substantially closer to experimental testing. To this end, Russell and his collaborators are currently making experimental model systems that recreate the serpentinization process, including the theory’s mineralogical membranes and chemical gradients."
Quotes and indented text were summarized from this link:
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