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Australian Scientists Discover New, Tiny Organisms

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 .]


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