Sun May 14 08:15:49 EST 1995
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In article <3p3tdc$gv at newsbf02.news.aol.com>,
petermsull at aol.com (PeterMSull) wrote:
>Forgive me for posting someone else's thoughts/writings on an important
>subject, but I believe the ideas put forth by Walter Lundby a few months
>back ( I save my sessions in this group for reference ) to be thought
>provoking at least. Sometimes it takes one outside the field to see
>something in a way in which people more "concentrated" otherwise may not.
>So please forgive me Walter, but I think your proposal has become even
>>Proposal: the reservoir for the Marburg and Ebola Reston viruses might
>be in a living being but in a clay, shale or petrified wood deposit.
That is a very interesting idea.
I agree that DNA and RNA can remain intact for a long time in clay or
unfortunately proteins and plasma membranes do not. Therefore, although
RNA could be embedded in clay, an intact viral partical could not, and
RNA is just another bunch of nucleotides without the rest of the viral
particle to get it into a host.
Having said that, the thinking here is very good. Conventional thoughts
how Ebola works and where it lives have turned up very little. A little
unconvetional thinking could go a long way.
Biochem/USC School of Medicine
chale at hsc.usc.edu
"But that's my opinion,
I could be wrong."
Clay may have been birthplace of life
Clay, a seemingly infertile blend of minerals, might have been the
birthplace of life on Earth. Or at least of the complex biochemicals that
make life possible, Cornell University biological engineers report in the
Nov. 7 online issue of the journal Scientific Reports, published by Nature
"We propose that in early geological history clay hydrogel provided a
confinement function for biomolecules and biochemical reactions," said Dan
Luo, professor of biological and environmental engineering and a member of
the Kavli Institute at Cornell for Nanoscale Science.
In simulated ancient seawater, clay forms a hydrogel - a mass of
microscopic spaces capable of soaking up liquids like a sponge. Over
billions of years, chemicals confined in those spaces could have carried
out the complex reactions that formed proteins, DNA and eventually all the
machinery that makes a living cell work. Clay hydrogels could have confined
and protected those chemical processes until the membrane that surrounds
living cells developed.
To further test the idea, the Luo group has demonstrated protein synthesis
in a clay hydrogel. The researchers previously used synthetic hydrogels as
a "cell-free" medium for protein production. Fill the spongy material with
DNA, amino acids, the right enzymes and a few bits of cellular machinery
and you can make the proteins for which the DNA encodes, just as you might
in a vat of cells.
To make the process useful for producing large quantities of proteins, as
in drug manufacturing, you need a lot of hydrogel, so the researchers set
out to find a cheaper way to make it. Postdoctoral researcher Dayong Yang
noticed that clay formed a hydrogel. Why consider clay? "It's dirt cheap,"
said Luo. Better yet, it turned out unexpectedly that using clay enhanced
But then it occurred to the researchers that what they had discovered might
answer a long-standing question about how biomolecules evolved. Experiments
by the late Carl Sagan of Cornell and others have shown that amino acids
and other biomolecules could have been formed in primordial oceans, drawing
energy from lightning or volcanic vents. But in the vast ocean, how could
these molecules come together often enough to assemble into more complex
structures, and what protected them from the harsh environment?
Scientists previously suggested that tiny balloons of fat or polymers might
have served as precursors of cell membranes. Clay is a promising
possibility because biomolecules tend to attach to its surface, and
theorists have shown that cytoplasm - the interior environment of a cell -
behaves much like a hydrogel. And, Luo said, a clay hydrogel better
protects its contents from damaging enzymes (called "nucleases") that might
dismantle DNA and other biomolecules.
>>>> and here
As further evidence, geological history shows that clay first appeared - as
silicates leached from rocks - just at the time biomolecules began to form
into protocells - cell-like structures, but incomplete - and eventually
membrane-enclosed cells. The geological events matched nicely with
How these biological machines evolved remains to be explained, Luo said.
For now his research group is working to understand why a clay hydrogel
works so well, with an eye to practical applications in cell-free protein
Luo collaborated with professor Max Lu of the Australian Institute for
Bioengineering and Nanotechnology at the University of Queensland in
Australia. The work was performed at the Cornell Center for Materials
Research Shared Facilities, supported by the National Science Foundation.