Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Transition metal catalysts could be key to origin of life, scientists report

06.09.2010
One of the big, unsolved problems in explaining how life arose on Earth is a chicken-and-egg paradox: How could the basic biochemicals—such as amino acids and nucleotides—have arisen before the biological catalysts (proteins or ribozymes) existed to carry out their formation?

In a paper appearing in the current issue of The Biological Bulletin, scientists propose that a third type of catalyst could have jumpstarted metabolism and life itself, deep in hydrothermal ocean vents.

According to the scientists' model, which is experimentally testable, molecular structures involving transition metal elements (iron, copper, nickel, etc.) and ligands (small organic molecules) could have catalyzed the synthesis of basic biochemicals (monomers) that acted as building blocks for more complex molecules, leading ultimately to the origin of life. The model has been put forth by Harold Morowitz of George Mason University (GMU), Vijayasarathy Srinivasan of GMU, and Eric Smith of the Santa Fe Institute.

"There has been a big problem in the origin of life (theory) for the last 50 years in that you need large protein molecules to be catalysts to make monomers, but you need monomers to make the catalysts," Morowitz says. However, he suggests, "You can start out with these small metal-ligand catalysts, and they'll build up the monomers that can be used to make the (large protein catalysts)."

A transition metal atom can act as the core of a metal-ligand complex, in which it is bound to and surrounded by other ligands. Morowitz and his colleagues propose that simple transition metal-ligand complexes in hydrothermal ocean vents catalyzed reactions that gave rise to more complex molecules. These increasingly complex molecules then acted as ligands in increasingly efficient transition metal-ligand complex catalysts. Gradually, the basic molecular ingredients of metabolism accumulated and were able to self-organize into networks of chemical reactions that laid the foundation for life.

"We used to think if we could understand what carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur were doing, we would immediately be able to understand biology," Morowitz says, listing elements that constitute a large proportion of Earth's biomass. "But now we're finding that these other fairly rare elements, transition metals, are necessary in biology, so we ask, 'What was their role in the origin of life?'"

The proposal suggests that the rise of life forms is a natural consequence of the unique properties of transition metals and ligand field theory, which describes the characteristics of ligand complexes.

"The idea has emerged from a study of the periodic table. We strongly feel that unless you're able to see how life comes about in some formal chemical way, you're never really going to solve the problem," Morowitz says.

Morowitz and his colleagues are preparing experiments to test the catalytic properties of transition metal-ligand complexes built with different types of ligands. Ligands known to bind tightly to transition metals include molecules produced during the course of the reductive citric acid cycle, a series of biochemical reactions essential for many microorganisms.

"We think life probably began with the reductive citric acid cycle, and there is evidence that under hydrothermal vent conditions some of the cycle's intermediates form," Morowitz says. "We are going to start with these molecules and mix them with various transition metals, cook them at different temperatures for a while, and see what kinds of catalysts we've made."

Such experiments could reveal what kinds of catalytic reactions took place to lay the foundations for life. The hypothesis also allows for the possibility that life could have arisen more than once.

"Life could have originated multiples times, and, if we find life elsewhere in the universe, it could be very similar to the life we know here because it will be based on the same transition metals and ligands," Morowitz says. "It's a conjecture at the moment, but it could become a formal scientific core for the emergence of life."

Citation:

Morowitz, H. J., Srinivasan, V., Smith, E. (2010) Ligand Field Theory and the Origin of Life as an Emergent Feature of the Periodic Table of Elements. Biol. Bull. 219: 1-6.

For a copy of this paper, please contact Carol Schachinger at cschachi@mbl.edu or visit The Biological Bulletin online at www.biolbull.org.

Published since 1897 by the Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts, The Biological Bulletin is one of America's oldest, peer-reviewed scientific journals. It publishes outstanding experimental research on the full range of biological topics and organisms, from the fields of Neuroscience, Behavior, Physiology, Ecology, Evolution, Development, Reproduction, Cell Biology, Biomechanics, Symbiosis, and Systematics; and it especially invites articles about those novel phenomena and contexts characteristic of intersecting fields. The electronic version, Biological Bulletin Online, contains the full content of each issue, including all figures and tables, beginning with the February 2001 issue. PDF files of the entire archive from 1897-2000 are also available.

The MBL is a leading international, independent, nonprofit institution dedicated to discovery and to improving the human condition through creative research and education in the biological, biomedical and environmental sciences. Founded in 1888 as the Marine Biological Laboratory, the MBL is the oldest private marine laboratory in the Western Hemisphere. For more information, visit www.MBL.edu

Carol Schachinger | EurekAlert!
Further information:
http://www.mbl.edu

More articles from Life Sciences:

nachricht Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>