Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Reconstructed ancient ocean reveals secrets about the origin of life

25.04.2014

Researchers from the University of Cambridge have published details about how the first organisms on Earth could have become metabolically active.

The results, which are reported in the journal Molecular Systems Biology, permit scientists to speculate how primitive cells learned to synthesize their organic components – the molecules that form RNA, lipids and amino acids. The findings also suggest an order for the sequence of events that led to the origin of life.


Alternative origins of metabolism

Molecular Systems Biology

A reconstruction of Earth's earliest ocean in the laboratory revealed the spontaneous occurrence of the chemical reactions used by modern cells to synthesize many of the crucial organic molecules of metabolism. Previously, it was assumed that these reactions were carried out in modern cells by metabolic enzymes, highly complex molecular machines that came into existence during the evolution of modern organisms.

Almost 4 billion years ago life on Earth began in iron-rich oceans that dominated the surface of the planet. An open question for scientists is when and how cellular metabolism, the network of chemical reactions necessary to produce nucleic acids, amino acids and lipids, the building blocks of life, appeared on the scene.

... more about:
»Biology »EMBO »Molecular »RNA »amino »metabolism »oceans »pathways »protein

The observed chemical reactions occurred in the absence of enzymes but were made possible by the chemical molecules found in the Archean sea. Finding a series of reactions that resembles the “core of cellular metabolism” suggests that metabolism predates the origin of life. This implies that, at least initially, metabolism may not have been shaped by evolution but by molecules like RNA formed through the chemical conditions that prevailed in the earliest oceans.

“Our results demonstrate that the conditions and molecules found in the Earth’s ancient oceans assisted and accelerated the interconversion of metabolites that in modern organisms make up glycolysis and the pentose-phosphate pathways, two of the essential and most centrally placed reaction cascades of metabolism,” says Dr. Markus Ralser, Group Leader at the Department of Biochemistry at the University of Cambridge and the National Institute for Medical Research.

“In our reconstructed version of the ancient Archean ocean, these metabolic reactions were particularly sensitive to the presence of ferrous iron that helped catalyze many of the chemical reactions that we observed.” From the analysis of early oceanic sediments, geoscientists such as Alexandra V. Turchyn from the Department of Earth Sciences at the University of Cambridge, one of the co-authors of the study, concluded that soluble forms of iron were one of the most frequently found molecules in the prebiotic oceans.

The scientists reconstructed the conditions of this prebiotic sea based on the composition of various early sediments described in the scientific literature. The different metabolites were incubated at high temperatures (50-90oC) similar to what might be expected close to a hydrothermal vent of an oceanic volcano, a temperature that would not support the activity of conventional protein enzymes. The chemical products were separated and analyzed by liquid chromatography tandem mass spectrometry. Some of the observed reactions could also take place in water but were accelerated by the presence of metals that served as catalysts.

“In the presence of iron and other compounds found in the oceanic sediments, 29 metabolic-like chemical reactions were observed, including those that produce some of the essential chemicals of metabolism, for example precursors of the building blocks of proteins or RNA,” says Ralser. “These results indicate that the basic architecture of the modern metabolic network could have originated from the chemical and physical constraints that existed on the prebiotic Earth.”

The detection of one of the metabolites, ribose 5-phosphate, in the reaction mixtures is particularly noteworthy. Its availability means that RNA precursors could in theory give rise to RNA molecules that encode information, catalyze chemical reactions and replicate.

Whether and how the first enzymes adopted the metal-catalyzed reactions described by the scientists remain to be established.

Non-enzymatic glycolysis and pentose phosphate pathway-like reactions in a plausible Archean ocean

Markus A. Keller, Alexandra V. Turchyn, Markus Ralser

Read the paper:
doi: 10.1002/msb.145228

http://msb.embopress.org/cgi/doi/10.1002/msb.20145228

Read the News and Views article by Pier Luigi Luisi:

doi: 10.1002/msb.145351

http://msb.embopress.org/cgi/doi/10.1002/msb.20145351

Further information on Molecular Systems Biology is available at http://msb.embopress.org

Media Contacts

Barry Whyte
Head | Public Relations and Communications
barry.whyte@embo.org

Thomas Lemberger
Chief Editor, Molecular Systems Biology
Tel: +49 6221 8891 413
thomas.lemberger@embo.org

About EMBO
EMBO is an organization of more than 1500 leading researchers that promotes excellence in the life sciences. The major goals of the organization are to support talented researchers at all stages of their careers, stimulate the exchange of scientific information, and help build a European research environment where scientists can achieve their best work.

EMBO helps young scientists to advance their research, promote their international reputations and ensure their mobility. Courses, workshops, conferences and scientific journals disseminate the latest research and offer training in techniques to maintain high standards of excellence in research practice. EMBO helps to shape science and research policy by seeking input and feedback from our community and by following closely the trends in science in Europe. 

For more information: www.embo.org

Yvonne Kaul | EMBO

Further reports about: Biology EMBO Molecular RNA amino metabolism oceans pathways protein

More articles from Life Sciences:

nachricht New Technique Maps Elusive Chemical Markers on Proteins
03.07.2015 | Salk Institute for Biological Studies

nachricht New approach to targeted cancer therapy
03.07.2015 | CECAD - Cluster of Excellence at the University of Cologne

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Viaducts with wind turbines, the new renewable energy source

Wind turbines could be installed under some of the biggest bridges on the road network to produce electricity. So it is confirmed by calculations carried out by a European researchers team, that have taken a viaduct in the Canary Islands as a reference. This concept could be applied in heavily built-up territories or natural areas with new constructions limitations.

The Juncal Viaduct, in Gran Canaria, has served as a reference for Spanish and British researchers to verify that the wind blowing between the pillars on this...

Im Focus: X-rays and electrons join forces to map catalytic reactions in real-time

New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions

A new technique pioneered at the U.S. Department of Energy's Brookhaven National Laboratory reveals atomic-scale changes during catalytic reactions in real...

Im Focus: Iron: A biological element?

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...

Im Focus: Thousands of Droplets for Diagnostics

Researchers develop new method enabling DNA molecules to be counted in just 30 minutes

A team of scientists including PhD student Friedrich Schuler from the Laboratory of MEMS Applications at the Department of Microsystems Engineering (IMTEK) of...

Im Focus: Bionic eye clinical trial results show long-term safety, efficacy vision-restoring implant

Patients using Argus II experienced significant improvement in visual function and quality of life

The three-year clinical trial results of the retinal implant popularly known as the "bionic eye," have proven the long-term efficacy, safety and reliability of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

World Conference on Regenerative Medicine: Abstract Submission has been extended to 24 June

16.06.2015 | Event News

MUSE hosting Europe’s largest science communication conference

11.06.2015 | Event News

 
Latest News

Siemens receives order for offshore wind power plant in Great Britain

03.07.2015 | Press release

'Déjà vu all over again:' Research shows 'mulch fungus' causes turfgrass disease

03.07.2015 | Agricultural and Forestry Science

Discovery points to a new path toward a universal flu vaccine

03.07.2015 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>