archiv~1.txt: SETI [ASTRO] Australian Scientists Discover New, Tiny Organisms

SETI [ASTRO] Australian Scientists Discover New, Tiny Organisms

Larry Klaes ( lklaes@bbn.com )
Mon, 22 Mar 1999 16:27:19 -0500

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>Date: Mon, 22 Mar 1999 19:59:11 GMT
>From: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
>To: astro@lists.mindspring.com
>Subject: [ASTRO] Australian Scientists Discover New, Tiny Organisms
>Sender: owner-astro@brickbat12.mindspring.com
>Reply-To: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
>
>University of Queensland
>Brisbane, Australia
>
>News release: 20 March 1999
>
>UQ scientists discover new, tiny organisms
>
>University of Queensland researchers have discovered novel miniature
organisms
>which call into question the minimum size for life as we know it on Earth.
>
>At 20 to 150 nanometres (billionths of a metre) in length, the organisms,
>which they call nanobes, are much smaller than the smallest certified
>terrestrial bacteria ever found on the planet.
>
>Researchers discovered the living colonies of organisms in ancient sandstones
>retrieved from an oil drilling site 3-5 km below the Australian seabed. The
>finding has been reported in a recent issue of American Mineralogist.
>
>The researchers behind the investigation are senior research fellow Dr
>Philippa Uwins and senior research officer Richard Webb of the University's
>Centre for Microscopy and Microanalysis (CMM), and PhD student Anthony Taylor
>of the CMM and Microbiology and Parasitology Department.
>
>They believe they may be the only research group in the world with actively
>growing nano-organisms.
>
>While studying sandstone samples from exploration wells several years ago,
>Dr Uwins discovered strange filaments on the rocks.
>
>"They were very small -- in the nano range, but we didn't know what they
>were," Dr Uwins said.
>
>In unfunded research, and exercising their scientific curiosity, they
>performed numerous tests using state-of-the art ultra high-resolution
>scanning electron microscopy, transmission electron microscopy, X-ray
>spectroscopy and DNA staining.
>
>The Lilliputian organisms were in the same size range but distinctly
>different from controversial fossil nanobacteria reported by NASA scientists
>in a Martian meteorite in 1996 and by other scientists in various rock types
>on Earth.
>
>Testing by the three Australian researchers has shown that the nanobes fulfil
>many criteria to qualify as biological life.
>
>Their colonies grew spontaneously, they contained genetic material (DNA)
>and their chemical and biological structures were consistent with life. For
>example, they were composed of biological materials such as carbon, oxygen
>and nitrogen, and they were membrane-bound structures surrounding a possible
>cytoplasm and nuclear area.
>
>In true scientific fashion, the scientists tried to disprove themselves by
>seeing if there could be another, plausible and non-biological explanation
>for the nanobes.
>
>They discounted many non-biological materials such as crystalline minerals,
>carbonates, fullerenes, carbon nano-tubes and non-living polymers and
>concluded it was difficult to propose any known non-biological materials
>which could account for the observed structures.
>
>Funding -- if only at a shoestring level -- was required to advance the
>project to the next level of investigation.
>
>In December, the project received $19,000 Australian Research Council small
>grant support for further molecular and structural analyses to determine
>whether the organisms were related to bacteria or fungi, or belonged to a
>different evolutionary tree altogether.
>
>"We will be the first group to perform DNA sequencing on a new life form with
>important and significant implications in many areas of research including
>molecular and cell biology, earth planetary sciences, environmental
>microbiology, medical microbiology, biotechnology, chemical engineering and
>many others," Dr Uwins said.
>
>"If it is proven beyond doubt scientifically that such small organisms exist,
>it will be a major contribution to the controversial debate concerning extra-
>terrestrial life and the origin of life on Earth and other planets."
>
>The debate was triggered in 1996 when NASA scientists in Houston reported the
>existence of fossil nano-organisms in a 4.5 billion-year-old, potato-sized
>Martian meteorite which crashed to Earth in Antarctica about 13,000 years
ago.
>
>They suggested that the meteorite, known as ALH84001, showed evidence of
>extra-terrestrial ancient life on Mars. The egg-shaped fossilised objects
>observed in the Mars meteorite were 20 to 100 nanometres long.
>
>The announcement caused U.S. Vice-President Albert Gore and then House
Speaker
>Newt Gingrich to agree on the need for more government spending and put Mars
>exploration on the front burner. One of the goals of the Mars exploration
>program now is to determine whether life started on Mars early in its
history.
>
>Critics of the NASA discovery argued that such nano life forms were too small
>to exist, because they had insufficient volume to contain the enzymatic and
>genetic material essential for life. They argued that the small size would
>not allow the supposed nanobacteria to contain RNA and a cell wall.
>
>The same criticisms were levelled at a number of scientists, including
>geologist Dr Robert Folk of the University of Texas who in 1993 reported that
>they could see the fossilised forms of ultrasmall microbes in many rocks and
>minerals found on Earth.
>
>Dr Folk argued that nanobacteria may have escaped biologists' notice because
>they eluded the conventional tools used to study bacteria.
>
>He said that 200 nanometres was both the smallest size visible with an
optical
>microscope, and the mesh size of the filters commonly used by microbiologists
>to strain out bacteria from liquids.
>
>It became standard microbiological thought, he said, that because no bacteria
>smaller than 200 nanometres were seen, that none existed. The smallest known
>bacteria to date are mycoplasma, minute bacteria which cause a common form
>of pneumonia, and which can be as small as 200 nanometres.
>
>Since their announcement, NASA scientists have searched for living
>nanobacteria on Earth.
>
>Dr Uwins said until now, there have been no living representatives for the
>Martian nano-organisms or other fossil nanobacteria described on Earth in
>various rock types.
>
>"Therefore it has been hard to convince the scientific community that the
>fossil Martian nanostructures could be remnant life forms," she said.
>
>Dr Uwins said factors that had made a big difference to the University of
>Queensland investigations had been the multi-disciplinary nature of the
>Centre for Microscopy and Microanalysis, and access to the $750,000 ultra
>high resolution Jeol 890 scanning electron microscope. The instrument is
>capable of one million times resolution, and is one of only a handful of
>such microscopes in the world.
>
>She said while the researchers did not yet have conclusive evidence for
>reproduction and metabolism in nanobes, and while they had not determined
>their evolutionary development, their evidence strongly suggested the
>existence of nanobes as biological organisms.
>
>Media:
>
>For further information, contact Dr Uwins, telephone work 07 3365 4694
>email: p.uwins@mailbox.uq.edu.au
>
>[Image caption: http://www.uq.edu.au/uni-news-media/Uwins.jpg]
>
>Dr Philippa Uwins with a photo of the nanobes that were first seen through
>at the ultra high resolution Jeol 890 scanning electron microscope.
>
>[NOTE: An image (493KB, 2000 x 2500 pixels) of the nanobes is available at
>http://photos.cc.uq.edu.au/UWINS/DCS00020.JPG .]
>
>
>