Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Component of volcanic gas may have played a significant role in the origins of life on Earth


Scientists at The Scripps Research Institute and the Salk Institute for Biological Studies are reporting a possible answer to a longstanding question in research on the origins of life on Earth--how did the first amino acids form the first peptides?

Peptides and proteins are strings of amino acid building blocks, and they are one of the most important classes of biological molecules found in living things today. Fifty years of chemical research on the origins of life has shown that amino acids could have formed spontaneously on the early Earth environment or could have been introduced onto the early Earth from meteorites.

"There are lots of ways to make amino acids," says Professor M. Reza Ghadiri, Ph.D., who is a member of The Skaggs Institute for Chemical Biology at Scripps Research. "But the question is, how do you couple them together?"

Ghadiri and Luke Leman, who is a member of the Kellogg School of Science and Technology at Scripps Research, worked out one possible solution with Leslie Orgel of the Salk Institute. In the latest issue of the journal Science, Leman, Ghadiri, and Orgel suggest that the missing link is a chemical component of volcanic gas known as carbonyl sulfide.

Carbonyl sulfide is present in volcanic gasses and deep sea vent emissions today, and since these geological phenomena were prominent features on the early Earth, it is reasonable to assume that the gas was present.

In their report, the scientists demonstrate that the gas can bring about a vigorous chemical reaction that forms peptides under mild aqueous conditions. Within a few minutes of introducing the gas to a reaction vessel containing amino acids, they observed high yields of di-, tri-, and tetra-peptides. They carried out the reaction in the presence of air, without air, and with and without other ingredients like metal ions, and they found peptides formed readily under all these conditions. "It’s really efficient, actually," says Ghadiri. "This addresses a very important question that we did not have a real good answer for."

Life--What We Know, and What We Don’t

The question of how life originated is one of the most interesting gaps in our knowledge--interesting perhaps because we know approximately when it occurred, but we do not know how it occurred.

The earliest fossils scientists have found are stromatolites--large clumps of cyanobacteria that grew in abundance in the ancient world over 3.5 billion years ago in what is now western Australia. These most likely evolved from some simpler life forms because, like all modern life, cyanobacteria are highly sophisticated living organisms--with cell walls, complex metabolism, and DNA genes. The question of the origins of life is: what came before the stromatolites?

Research on the origins of life has suggested the notion of an ancient RNA world--one in which RNA genes stored genetic information (something done by DNA today), carried out the chemistry necessary for life, and formed the essential physical structures of life (something done primarily by proteins today).

But how did that RNA world come about?

"Anybody who thinks they know the solution to this problem [of the origin of life] is deluded," says Orgel. "But," he adds, "anybody who thinks this is an insoluble problem is also deluded."

One possible approach to the problem of life’s origins is to ask the question scientifically rather than historically-- how can life emerge rather than how did life emerge. In order to address this, scientists try to determine experimentally what is chemically feasible and what could have occurred on the prebiotic earth.

One possibility, which was suggested in the 1920s by the Russian scientist A.I. Oparin, is that life emerged in its most primitive forms from minerals, metals, and the elements carbon, hydrogen, oxygen, and nitrogen, which were combined into amino acids, nucleotides, and the other the building blocks of life under the violent energy of lightning, solar radiation, comet impacts, and volcanic events that were present.

In 1953, this theory was given a boost when a paper was published in Science by Stanley L. Miller, who is Professor Emeritus at the University of California, San Diego. In the paper, Miller described an experiment he devised with Harold C. Urey--now called the Miller and Urey experiment--that gave experimental underpinnings to Oparin’s ideas.

In the experiment, Miller boiled H2O, CH4,H2, and NH3 gases in a glass apparatus containing a pair of tungsten electrodes. He subjected the chemicals to an electric discharge, intended to simulate conditions on the early Earth, and he collected and analyzed the molecules that formed--which included the amino acids alanine, glycine, and a few others. In the years since, several other investigators have expanded on the Miller–Urey experiment to demonstrate the formation and chemistry of many of the common biological amino acids, sugars, and nucleotides. Orgel, who is a long-time investigator in the field, has done pioneering research on the prebiotic chemistry of nucleotides.

This latest study is an advance because previous attempts to demonstrate the formation of peptides on early Earth depended on reaction schemes that were less plausible or were not as efficient. Next, the team plans to examine carbonyl sulfide’s reactive properties further and see if the gas can bring about other chemical reactions that are relevant to prebiotic chemistry.

Jason Bardi | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Make way for the mini flying machines
21.03.2018 | American Chemical Society

nachricht New 4-D printer could reshape the world we live in
21.03.2018 | American Chemical Society

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

TRAPPIST-1 planets provide clues to the nature of habitable worlds

21.03.2018 | Physics and Astronomy

The search for dark matter widens

21.03.2018 | Materials Sciences

Natural enemies reduce pesticide use

21.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>