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"Mind-Boggling!" --New Non-Biological Theory of Origins of Life

 

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"Modern metabolism has a precursor, a template, that was non-biological," says Greg Springsteen, first author of the new study at Furman University.

Chemists at The Scripps Research Institute (TSRI) have developed a fascinating new theory for how life on Earth may have begun. Their experiments, described today in the journal Nature Communications, demonstrate that key chemical reactions that support life today could have been carried out with ingredients likely present on the planet four billion years ago.

 

"This was a black box for us," said Ramanarayanan Krishnamurthy, PhD, associate professor of chemistry at TSRI and senior author of the new study. "But if you focus on the chemistry, the questions of origins of life become less daunting."

For the new study, Krishnamurthy and his coauthors, who are all members of the National Science Foundation/National Aeronautics and Space Administration Center for Chemical Evolution, focused on a series of chemical reactions that make up what researchers refer to as the citric acid cycle.

Every aerobic organism, from flamingoes to fungi, relies on the citric acid cycle to release stored energy in cells. In previous studies, researchers imagined early life using the same molecules for the citric acid cycle as life uses today. The problem with that approach, Krishnamurthy explai20ns, is that these biological molecules are fragile and the chemical reactions used in the cycle would not have existed in the first billion years of Earth—the ingredients simply didn't exist yet.

Leaders of the new study started with the chemical reactions first. They wrote the recipe and then determined which molecules present on early Earth could have worked as ingredients.

 

 

The new study outlines how two non-biological cycles—called the HKG cycle and the malonate cycle—could have come together to kick-start a crude version of the citric acid cycle. The two cycles use reactions that perform the same fundamental chemistry of a-ketoacids and b-ketoacids as in the citric acid cycle. These shared reactions include aldol additions, which bring new source molecules into the cycles, as well as beta and oxidative decarboxylations, which release the molecules as carbon dioxide (CO2).

As they ran these reactions, the researchers found they could produce amino acids in addition to CO2, which are also the end products of the citric acid cycle. The researchers think that as biological molecules like enzymes became available, they could have led to the replacement of non-biological molecules in these fundamental reactions to make them more elaborate and efficient.

"The chemistry could have stayed the same over time, it was just the nature of the molecules that changed," says Krishnamurthy. "The molecules evolved to be more complicated over time based on what biology needed."

Making these reactions even more plausible is the fact that at the center of these reactions is a molecule called glyoxylate, which studies show could have been available on early Earth and is part of the citric acid cycle today (called the "Glyoxylate shunt or cycle").

Krishnamurthy says more research needs to be done to see how these chemical reactions could have become as sustainable as the citric acid cycle is today.

The Daily Galaxy via The Scripps Research Institute

Image credit: ISS and UOregon.Edu

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Comments

...so why can't they prove this in the lab or not? Just start with Non living chemistry and end up with some simple form of life... Either you can do it or you can't. I don't think you can guarantee that is how life started on Earth for sure if it works (unless you can prove nothing else is possible)... but if you can't reproduce it in the lab first, then you can't even get past possible to probable IMHO.

Knowing science very well, let me give you the scientific method:

1: Observe or measure a natural phenomenon in process

2: Analyze your observation

3: Make a theory about its functioning

4: Predict an outcome of an experiment you derived from that theory

5: Conduct the experiment and check if your prediction fits the outcome of that experiment

6: If the outcome doesn't fit your prediction, revise your theory or throw it in the garbage

7: If the outcome fits your prediction, let independent researchers repeat the experiment to exclude any mistakes! Not before all of the above steps are done, one can claim something scientifically evidenced, let alone proven!
Evolution can neither be observed, predicted, experimentally verified nor be repeated!
It must rely on hypotetico-deductive, which is by no means able to evidence anything else but presuppositions! All that can be verified is adaptation by variation according to the Mendelian Laws of inheritance in conjunction with the epigenetic program.
If you think you have any evidence for evolution that pleases this method, you need a lighter to see the sun!
I challenge you to get me JUST ONE piece of evidence for the origine of life or evolution that pleases this method!

Open your minds people. Maybe, just maybe, an experiment can create life except that you have to let the experiment continue to run for a few hundred million years. So, they can be right but be unable to prove it today or tomorrow.

Or does anyone think you can create a monkey in a test tube by adding all the ingredients together and shaking and baking for 30 minutes at 325 degrees? Any proponents that life began from chemicals brought together by chance and struck by lightening and bingo "it's alive, it's alive!"

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