Navigation Links
ASU researcher may have discovered key to life before its origin on Earth
Date:2/28/2008

TEMPE, ARIZ. -- An important discovery has been made with respect to the mystery of handedness in biomolecules. Researchers led by Sandra Pizzarello, a research professor at Arizona State University, found that some of the possible abiotic precursors to the origin of life on Earth have been shown to carry handedness in a larger number than previously thought.

The work is being published in this weeks Early Edition of the Proceedings of the National Academy of Sciences (PNAS). The paper is titled, Molecular asymmetry in extraterrestrial chemistry: Insights from a pristine meteorite, and is co-authored by Pizzarello and Yongsong Huang and Marcelo Alexandre, of Brown University.

Pizzarello, in ASUs Department of Chemistry and Biochemistry, worked with Huang and Alexandre in studying the organic materials of a special group of meteorites that contain among a variety of compounds, amino acids that have identical counterparts in terrestrial biomolecules. These meteorites are fragments of asteroids that are about the same age as the solar system (roughly 4.5 billion years.)

Scientists have long known that most compounds in living things exist in mirror-image forms. The two forms are like hands; one is a mirror reflection of the other. They are different, cannot be superimposed, yet identical in their parts.

When scientists synthesize these molecules in the laboratory, half of a sample turns out to be left-handed and the other half right-handed. But amino acids, which are the building blocks of terrestrial proteins, are all left-handed, while the sugars of DNA and RNA are right-handed. The mystery as to why this is the case, parallels in many of its queries those that surround the origin of life, said Pizzarello.

Years ago Pizzarello and ASU professor emeritus John Cronin analyzed amino acids from the Murchison meteorite (which landed in Australia in 1969) that were unknown on Earth, hence solving the problem of any contamination. They discovered a preponderance of left-handed amino acids over their right-handed form.

The findings of Cronin and Pizzarello are probably the first demonstration that there may be natural processes in the cosmos that generate a preferred amino acid handedness, Jeffrey Bada of the Scripps Institution of Oceanography, La Jolla, Calif., said at the time.

The new PNAS work was made possible by the finding in Antarctica of an exceptionally pristine meteorite. Antarctic ices are good curators of meteorites. After a meteorite falls -- and meteorites have been falling throughout the history of Earth -- it is quickly covered by snow and buried in the ice. Because these ices are in constant motion, when they come to a mountain, they will flow over the hill and bring meteorites to the surface.

Thanks to the pristine nature of this meteorite, we were able to demonstrate that other extraterrestrial amino acids carry the left-handed excesses in meteorites and, above all, that these excesses appear to signify that their precursor molecules, the aldehydes, also carried such excesses, Pizzarello said. In other words, a molecular trait that defines life seems to have broader distribution as well as a long cosmic lineage.

This study may provide an important clue to the origin of molecular asymmetry, added Brown associate professor and co-author Huang.


'/>"/>

Contact: Skip Derra
skip.derra@asu.edu
480-965-4823
Arizona State University
Source:Eurekalert

Related biology news :

1. Electronic structure of DNA revealed for 1st time by Hebrew University and collaborating researchers
2. Researchers offer new theory for dogfish and skate population outburst on Georges Bank
3. UCLA researchers solve decade-old mystery
4. Rats on islands disrupt ecosystems from land to sea, researchers find
5. Iowa State researchers help piece together the corn genomes first draft
6. U-M researchers release most detailed global study of genetic variation
7. LSU researchers challenge analyses on sustainability of Gulf fisheries
8. Researchers probe a DNA repair enzyme
9. Managing uncertainty important in ecological balance: ASU researcher
10. Oregon researchers study widespread areas of low oxygen off northwest coast
11. Stanford researchers say living corals thousands of years old hold clues to past climate changes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/7/2016)... TORONTO , June 7, 2016  Syngrafii ... begun a business relationship that includes integrating Syngrafii,s ... pilot branch project. This collaboration will result in ... for the credit union, while maintaining existing document ... http://photos.prnewswire.com/prnh/20160606/375871LOGO ...
(Date:6/1/2016)... Favorable Government Initiatives Coupled With ... Identification to Boost Global Biometrics System Market Through 2021  ... report, " Global Biometrics Market By Type, By ... 2011 - 2021", the global biometrics market is projected ... of growing security concerns across various end use sectors ...
(Date:5/9/2016)... May 9, 2016 Elevay is ... to expanding freedom for high net worth professionals seeking ... today,s globally connected world, there is still no substitute ... ever duplicate sealing your deal with a firm handshake. ... by taking advantage of citizenship via investment programs like ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... Rolf K. Hoffmann, former senior ... the University of North Carolina Kenan-Flagler Business School effective June 27. ... Kenan-Flagler, with a focus on the school’s international efforts, leading classes and participating ...
(Date:6/24/2016)... , June 24, 2016 Epic Sciences ... detects cancers susceptible to PARP inhibitors by targeting ... cells (CTCs). The new test has already been ... in multiple cancer types. Over 230 ... damage response pathways, including PARP, ATM, ATR, DNA-PK ...
(Date:6/23/2016)... WI (PRWEB) , ... June 23, 2016 , ... ... supplements, is pleased to announce the launch of their brand, UP4™ Probiotics, into ... for over 35 years, is proud to add Target to its list of ...
(Date:6/23/2016)... Houston Methodist Willowbrook Hospital has signed ... to serve as their official health care provider. ... will provide sponsorship support, athletic training services, and ... volunteers, athletes and families. "We are ... and to bring Houston Methodist quality services and ...
Breaking Biology Technology: