[meteorite-list] NPA 12-07-1970 Non-Earthly Amino Acids, Murchison

From: MARK BOSTICK <thebigcollector_at_meteoritecentral.com>
Date: Sun Feb 20 21:04:03 2005
Message-ID: <BAY104-F39EA3CAD4337C22E0A7D9FB3610_at_phx.gbl>

Paper: The News
City: Frederick, Maryland
Date: Monday, December 7, 1970
Page: C-4

Non-Earthly Amino Acids Identified By Scientists

     The first positive identification of amino acids of extraterrestrial
(non-earthly) origin has been made by scientists of the National Aeronautics
and Space Administration's Ames Research Center, Mountain View, Calif.
     The find, according to Ames' Dr. Cyril Ponnamperuma, is probably the
first conclusive proof of extraterrestrial chemical evolution, the chemical
processes which precede the origin of life.
     The amino acids, among the principal constituents of living cells were
found in abundance in a meteorite which fell near Murchison, Victoria,
Australia, on Sept. 28, 1969. The discovery was confirmed by a battery of
laboratory tests and is reported in the current edition of NATURE.
     The work was done on material taken from a meteorite identified as a
Class II carbonaceous chondrite whose impact near Murchison was
observed.vvScientists believe that this type of meteorite originates in the
asteroid belt.
     The find has three major aspects, according to Dr. Ponnamperuma.
     It is strong new evidence for the theory of chemical evolution, it
suggests the possible existence of life elsewhere in the universe, resulting
from chemical evolution, and it may provide a new time sequence for the
origin of life on Earth and elsewhere in the universe.
     The find was made by a team of Ames researchers headed by Dr.
Ponnamperuma. Important parts of the work were also done by Dr. Ian R.
Kaplan of the University of California as Los Angeles and Dr. Carleton
Moore, Director of the Center for Meteorite Studies, of Arizona State
University.
     The theory of chemical evolution states that, starting with the basic
elements of the primordial universe, various types of energy discharges
caused, ever - more complex chemical molecules to evolve. After hundreds of
millions of yeas of chemical evolution, very complex molecules appeared
which could reproduce themselves and thus could be considered the first
forms of life.
     Amino acids are basic constituents of living cells. However, the amino
acids found in the Murchison meteorite do not appear to be of biological
origin. Neither do other complex organic molecules (various hydrocarbons)
also found in the meteorite.
     The discovery of these non-biological amino acids in the meteorite
shows: (1) - that building blocks of life such as amino acids can form by
chemical means in nature, (2) - that these complex molecules can form away
from the Earth - in other parts of the solar system, and presumably
elsewhere in the universe, and (3) - that the discovery appears to set a
time sequence.
     Scientists believe that the planets of the solar system, including the
Earth, formed 4.5 billion years ago from an interstellar gas cloud. The
Murchison, like virtually all other meteorites, is 4.5 billion years old.
     Finding of amino acids and other complex organic molecules in the
Murchison meteorite strongly suggests that these complex life materials have
been present from the time of formation of the Earth.
     The Ames discovery is not the first report of amino acids and
hydrocarbons in meteorites. But other reports have been seriously
criticized because of the fact that biological materials may have gotten
into the meteorites after their impact with Earth.
     Although Earthly contamination of the Murchison meteorite cannot be
rigorously ruled out, its case differs because of a number of proofs of
non-biological and non-Earthly origin resulting from the precise
identifications made in the Ames' work.
     The researchers found five of the 20 amino acids normally found in
living cells. Along with them, they found 11 other amino acids in good
quantity - compounds structurally almost identical to the protein - forming
amino acids but having no functional role in living organisms.
     Still more evidence for non-biological and non-Earthly origin is that
biological-type hydrocarbons also were found mixed with non-biological
hydrocarbons. These were in proportions similar to those found in Dr.
Ponnamperuma's experiments at Ames which simulate the process of chemical
evolution in the laboratory.
     "The amino acids found were of the almost equal mixture both D and L
types (right and light-handed molecule structures). Amino acids of
biological origin, like those found on Earth, are all of the left-handed
variety." Dr. Ponnamperuma said. "Biologists can imagine that life on
another planet could be based on right-handed amino acids instead.
     But they agree that a mixture of both types virtually rules out
biological origin. Right-handed amino acids are very rarely found on Earth
because Earth organisms produce only left-handed amino acids."
     Finally, a far higher proportion of the heavy isotope carbon 13 was
found than would have been found in Earthly biological material. Earth
organisms contain relatively little carbon 13 due to fractionation during
photosynthesis.
     The identification of the materials in the Murchison meteorite was made
by gas chromatography combined with mass spectrometry, among the most
precise methods known for exact identifications of complex chemicals.

(end)

Clear Skies,
Mark Bostick
Wichita, Kansas
http://www.meteoritearticles.com
http://www.kansasmeteoritesociety.com
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PDF copy of this article, and most I post (and about 1/2 of those on my
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The NPA in the subject line, stands for Newspaper Article. The old list
server allowed us a search feature the current does not, so I guess this is
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Received on Sun 20 Feb 2005 09:03:52 PM PST