Scientists Discover New Clue to Chemical Origins of Life

[geomancer]

https://www.sciencedaily.com/release...0124092930.htm

Scientists Discover New Clue to Chemical Origins of Life

ScienceDaily (Jan. 24, 2012) — Organic chemists at the University of York have made a significant advance towards establishing the origin of the carbohydrates (sugars) that form the building blocks of life.

A team led by Dr Paul Clarke in the Department of Chemistry at York has re-created a process which could have occurred in the prebiotic world.

Working with colleagues at the University of Nottingham, they have made the first step towards showing how simple sugars -- threose and erythrose -- developed. The research is published in Organic & Biomolecular Chemistry.
All biological molecules have an ability to exist as left-handed forms or right-handed forms. All sugars in biology are made up of the right-handed form of molecules and yet all the amino acids that make up the peptides and proteins are made up of the left-handed form.

The researchers found using simple left-handed amino acids to catalyse the formation of sugars resulted in the production of predominately right-handed form of sugars. It could explain how carbohydrates originated and why the right-handed form dominates in nature.

Dr Clarke said: "There are a lot of fundamental questions about the origins of life and many people think they are questions about biology. But for life to have evolved, you have to have a moment when non-living things become living -- everything up to that point is chemistry.

"We are trying to understand the chemical origins of life. One of the interesting questions is where carbohydrates come from because they are the building blocks of DNA and RNA. What we have achieved is the first step on that pathway to show how simple sugars -- threose and erythrose -- originated. We generated these sugars from a very simple set of materials that most scientists believe were around at the time that life began."

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Story Source:

The above story is reprinted from materials provided byUniversity of York, via AlphaGalileo.
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Journal Reference:

1. Laurence Burroughs, Paul A. Clarke, Henrietta Forintos, James A. R. Gilks, Christopher J. Hayes, Matthew E. Vale, William Wade, Myriam Zbytniewski. Asymmetric organocatalytic formation of protected and unprotected tetroses under potentially prebiotic conditions. Organic & Biomolecular Chemistry, 2012; DOI:10.1039/C1OB06798B

[occihoff]

https://www.sciencedaily.com/release...0124092930.htm

Scientists Discover New Clue to Chemical Origins of Life
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Dr. Clarke says:

"But for life to have evolved, you have to have a moment when non-living things become living -- everything up to that point is chemistry." [Italics mine]

I question the idea of such a "moment." It seems to me that the transition between what we would conceive of as "living" and "non-living" entities is more vague and gradual.

It seems that viruses are the entities that form this transition. Viruses are "living" in the sense that they contain or are basically constituted by simple strands of DNA molecules. These little packets of DNA can dissolve the outer membranes of living cells, enter the cytoplasm, and "use" the cytoplasm to multiply into more packets of DNA. In this regard viruses seem to exhibit something like DNA molecules with "behavior" and thus constitute the most fundamental essence of what we would consider "living" beings.

But viruses are really more like crystals than what we would ordinarily conceive of as living beings. They are like crystals made of DNA molecules. Ordinary non-DNA crystals such as quartz and other minerals also multiply, given the right conditions. But we would never think of them as living. They simply respond to basic conditions of molecular attraction. In this sense viruses are more like crystals made of DNA molecules than they are like what we would think of as living entities.

So to put it in Dr. Clarke's terms, are viruses "living" things, or "non-living" things? "Chemistry" or "non-chemistry?" "Moment" or sort of blurry transitional state?

I find the wonder and mystery of this transitional state of matter to be incomprehensibly fascinating and defiant of straightforward intellectual categorization!