Posted on 01/10/2004 8:05:30 AM PST by PatrickHenry
GAINESVILLE, Fla. --- Researchers at the University of Florida say they have shown that minerals were key to some of the initial processes that formed life on Earth. Specifically, a borax-containing mineral known as colemanite helps convert organic molecules found in interstellar dust clouds into a sugar, known as ribose, central to the genetic material called RNA. This announcement provides a key step toward solving the 3-billion-year-old mystery of how life on Earth began. The findings will appear in Friday's issue of the journal Science. Steven Benner, Alonso Ricardo, Matthew Carrigan and Alison Olcott built on a famous experiment done 50 years earlier by Stanley Miller that is found in many textbooks. In 1953, Miller showed that electric sparks in a primitive atmosphere made amino acids, the building blocks of proteins.
Miller's experiment failed to identify sugars that were needed for genetic material, however. "The sugar ribose can be formed from interstellar precursors under prebiotic conditions," said Benner, who led the research funded by NASA, the National Science Foundation and The Agouron Institute in Pasadena, Calif. "But ribose is too unstable to survive under Miller's conditions." Ribose, like most sugars, turns into tar if not handled carefully. "It is like baking a cake too long," said Benner, a UF distinguished professor of chemistry and anatomy and cell biology. In 1995, Miller gave up trying to make ribose prebiotically, writing: "The first genetic material could not have contained ribose or other sugars because of their instability."
Benner, who also is a member of NASA's Astrobiology Institute, did the first experiments as an instructor at an international geobiology course last summer funded by the Agouron Institute and held at the University of Southern California Wrigley Institute for Environmental Studies. "We asked two questions. First, what simple organic molecules might have been present on early Earth as starting materials to form ribose? Then, what might have been present on early Earth to capture ribose and keep it from burning up like overcooked cake?" Benner said.
To identify simple organic molecules that might be the starting materials, Benner turned to compounds known to exist in interstellar dust, such as formaldehyde, used to preserve tissue. "Formaldehyde may not seem to be a good starting point for the life that we know," he said. "But it is simple. With only one carbon atom, one oxygen atom and two hydrogen atoms, there is a lot of formaldehyde to work with in the cosmos."
Benner and his team showed that formaldehyde, with other interstellar compounds, could form ribose and other sugars when treated in the presence of base materials such as lime, a material used to adjust the pH level of lawns, among other things. Lime was effective, but the ribose decomposed soon after it was formed.
Recognizing that ribose had a particular chemical structure that allowed it to bind to minerals containing the element boron, they turned to another substance called colemanite. "Colemanite is a mineral containing borate found in Death Valley," he said. "Without it, ribose turns into a brown tar. With it, ribose and other sugars emerge as clean products." Benner then showed similar reactions with other borate minerals, including ulexite and kernite, which is more commonly known as borax.
Benner and his team are the first researchers to succeed in making significant amounts of ribose under these early conditions.
Joseph Piccirilli, a biological chemist at the Howard Hughes Medical Institute and the University of Chicago, said Benner's work "has simplicity and brilliance."
"Organic chemists have long known that borate complexes with compounds like ribose," Piccirilli said, "and prebiotic scientists have long believed that minerals on the early Earth played an important role in the origin of life." Until now, "no one has put the two ideas together," he said.
"We are not claiming that this is how life started," Benner stressed. "We are saying that we have demonstrated a recipe to make a key part of life without any biochemical machinery. The more recipes of this type that can be found, the more clues we have about how life could have actually gotten started on the primitive Earth."
While best classified as basic science, the work has practical biological and medical value. "Curiously, thinking about how life originated and what form it might take on other planets helps us design new tools for disease diagnostics and therapy," Benner said. Diagnostic tools enabled by Benner's work seeking alternative life forms are used today in the clinic to monitor the load of the viruses that cause AIDS and hepatitis C.
The work also complements other research Benner is conducting that focuses on ancient forms of life on Earth. In a September report in Nature, Benner and his collaborators deduced the structure of a protein found in a bacterium that lived several billion years ago and resurrected the ancient protein. By studying it in the laboratory, the group inferred the ancient bacteria lived in a hot spring at about 150 degrees Fahrenheit.
With the prebiotic experiments, Benner said, "we are working forward in time, from the origin of the planet to the first life. With experiments with ancient proteins, we work backwards in time, from the modern world to the most primitive of bacteria." The group's goal, he said, is to have the two meet in the middle.
There isn't much that is layman oriented. You can find quite a number of geology papers on crude oil finds in Nevada on Google. In Nevada, gold and oil are often intertwined, as they are both associated with the hydrothermal systems there. In fact, many abandoned gold mines will slowly backfill with crude seeping out of the shaft walls. Most people aren't even aware that Nevada has oil, though its most productive oil well has produced over 20 million barrels so far. What is special about Nevada crude, is that it is found in extremely young geological formations, too young to even have crude by conventional theory.
The specific association of crude oil formation and stable hydrothermal systems was largely discovered in the 1990s. The short story: With the discovery of the massive Carlin trend gold deposit in Nevada by a couple research geologists, an old extinct hydrothermal structure, some significant changes in theory took place as to where and how gold deposits formed. A causal factor that had been missed was long and strong hydrothermal activity in the local geology, if not currently, at one time in the past. In Nevada, you can't take a leak without hitting a hydrothermal system or volcanic gas vent -- it is a major part of the geology -- but nobody ever takes core samples from active hydrothermal beds because it eats coring rigs alive and is therefore extremely expensive. Many of the active hydrothermal systems in Nevada are very old, plenty long for gold deposits to form. Consequently, in the 1990s many of the gold prospecting companies started coring active hydrothermal beds looking for gold deposits; by their new models there should be dozens of rich new deposits in the active hydrothermal beds that had never been discovered because it had always been either too dangerous or too expensive to look in those places without good reason to do so. Most of the classic ultra-rich gold fields of Nevada are on the peripheries of major active hydrothermal systems.
As these companies started coring the actual hydrothermal beds and hot springs in the old gold fields, they discovered something else. They pulled up crude oil as often as they pulled up gold. That bits of crude were scattered all over Nevada was well-known, but they did not expect to find it in the hydrothermal beds, and certainly not in the fashion in which they were finding it. The major hot spring near my ranch in Nevada is one of the many places where they pulled up gobs of crude when coring for gold.
The current theory is that the unusual catalytic mineralogy of these regions, combined with the very hot and active hydrothermal systems providing energy and transport, is actively manufacturing crude oil and all manner of complex organic carbon compounds. It isn't a commercially viable source for crude, but it gives a fair amount of insight into the speed and nature of crude formation. On the other hand, there are a bunch of new commercial gold deposits pending in Nevada (already one of the world's major gold exporting regions) as a result of studying hydrothermal systems.
Is this essay of Ichneumon's among your INTREPs?
Huh. And it took about 250 years for the Church to accept that the Earth goes around the sun, and stop murdering those who said so.
And after 150 years they're still trying to find a single instance that would confirm Darwin's theory of general evolution.
An instance that would pursuade a dyed-in-the-wool creationist, I assume you mean.
He specifically mentioned "Darwin's theory of general evolution." Presumably, he has no problem with special evolution.
And if an explosion occurred next to this rock that has a flat edge projecting from it, then it could have caused the rock to turn resulting in a screw being driven into my automobile.
I am not claiming that this is how autombiles started," DannyTN stressed. "I am saying that I have demonstrated a recipe to make a key part of my autombile without any biochemical machinery.
All that formaldehyde might explain why people lived so long in Biblical ages, before evolutionary processes gave us the advantage of shortened lives.
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