Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Critical Pairing - Origin of life: the search for the first genetic material

17.11.2006
How did life originate on Earth?

Until now, there have only been theories to answer this question. One of the fundamental steps leading to living organisms is the development of molecules that can replicate and multiply themselves—the first genetic material. A team led by Ramanarayanan Krishnamurthy and Albert Eschenmoser at The Scripps Research Institute in La Jolla, California, is researching how this molecule might have looked.

Our own genetic material is DNA. Its backbone is made of sugar and phosphate building blocks. Like a strand of pearls, the four “letters” of the genetic code are arranged along this backbone. Two complementary strands of DNA form a double helix because the purine bases adenine (A) and guanine (G) form specific pairs with the pyrimidine bases thymine (T) and cytosine (C), attaching to each other through two or three docking sites. This type of structure could also be the basis for the first genetic material. However, it is doubtful that its backbone consisted of sugar and phosphate; it may have consisted of peptide-like building blocks. Amino acids, from which peptides are made, were already present in the “primordial soup”. However, the bases may also have looked different in their primitive form.

To find the right track in searching for the origins of life, the team is trying to put together groups of potential building blocks from which primitive molecular information transmitters could have been made. The researchers have taken a pragmatic approach to their experiments. Compounds that they test do not need to fulfill specific chemical criteria; instead, they must pass their “genetic information” on to subsequent generations just as simply as the genetic molecules we know today—and their formation must have been possible under prebiotic conditions. Experiments with molecules related to the usual pyrimidine bases (pyrimidine is a six-membered aromatic ring containing four carbon and two nitrogen atoms), among others, seemed a good place to start. The team thus tried compounds with a triazine core (a six-membered aromatic ring made of three carbon and three nitrogen atoms) or aminopyridine core (which has an additional nitrogen- and hydrogen-containing side group). Imitating the structures of the normal bases, the researchers equipped these with different arrangements of nitrogen- and hydrogen- and/or oxygen-containing side groups.

... more about:
»Backbone »Genetic »genetic material

Unlike the usual bases, these components can easily be attached to many different types of backbone, for example, a backbone made of dipeptides or other peptide-like molecules. In this way, the researchers did indeed obtain molecules that could form specific base pairs not only with each other, but also with complementary RNA and DNA strands. Interestingly, only one sufficiently strong pair was formed within both the triazine and aminopyridine families; however, for a four-letter system analogous to the ACGT code, two such strongly binding pairs are necessary. “Our results indicate that the structure of the bases, rather than the structure of the backbone, was the critical factor in the development of our modern genetic material,” says Krishnamurthy. Many chain molecules are able to adopt a suitable spatial structure, but only a few bases can enter into the necessary specific pairing. In this, our alternative bases are clearly inferior to the usual Watson–Crick bases. “Based on our observations, we are beginning to understand why the natural bases are optimal with regard to the function they perform.”

Author: Ramanarayanan Krishnamurthy, The Scripps Research Institute, La Jolla, (USA), mailto:rkrishna@scripps.edu

Title: Mapping the Landscape of Potentially Primordial Informational Oligomers: Oligodipeptides and Oligodipeptoids Tagged with Triazines as Recognition Elements / Mapping the Landscape of Potentially Primordial Informational Oligomers: Oligodipeptides Tagged with 2,4-Disubstituted 5-Aminopyrimidines as Recognition Elements

Angewandte Chemie International Edition, doi: 10.1002/anie.200603207

Ramanarayanan Krishnamurthy | Angewandte Chemie
Further information:
http://www.angewandte.de
http://www.scripps.edu

Further reports about: Backbone Genetic genetic material

More articles from Life Sciences:

nachricht Cnidarians remotely control bacteria
21.09.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Immune cells may heal bleeding brain after strokes
21.09.2017 | NIH/National Institute of Neurological Disorders and Stroke

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Comet or asteroid? Hubble discovers that a unique object is a binary

21.09.2017 | Physics and Astronomy

Cnidarians remotely control bacteria

21.09.2017 | Life Sciences

Monitoring the heart's mitochondria to predict cardiac arrest?

21.09.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>