lief@hpfcrs.UUCP (lief) (04/18/85)
I am curious as to what the latest and greatest evolutionary stand is on
"Spontaneous Generation". The article that Paul mentioned, which appeared in
several newspapers, suggests that some folks are pushing for CLAY as the media
for "Spontaneous Generation". Is this being seriously persued? Or is it a
hoax?
I believe that the notion of life arising from a chemical soup in the
oceans is prevalent. However, I do believe this aqueous media does present
some difficulties so it would not surprise me if several folks are trying to
find an alternate media for "Spontaneous Generation".
The main problem with an aqueous media is the isoelectric precipitation
of proteins. The solubility of most globular proteins is profoundly influenced
by the pH of the surrounding system. On either side of this critical pH, the
solubility rises very sharply. Nearly all globular proteins show a solubility
minimum, although the pH at which it occurs varies from one protein to another.
The pH at which a protein is least soluble is its isoelectric pH, defined
as that pH at which the molecule has no net electric charge and fails to move
in an electric field. However, at pH values above or below the isoelectric
point, all the protein molecules have a net charge of the same sign. They
therefore repel each other, preventing coalescence of single molecules into
insoluble aggregates. It is this fact that proteins are electrolytes of very
large molecular weight that enables one to seperate mixtures of proteins.
For example, the isoelectric pH of Pepsin is ~1.0, Urease is 5.0,
Hemoglobin is 6.8, Cytochrome c is 10.6, etc. For more details on the
above information, refer to Lehninger's Biochemistry textbook, 2nd ed., p162.
In otherwords, in an aqueous media, with a pH of around 7 or thereabouts,
the only proteins that could possibly coalesce and form life would need to
have similar isoelectric points which would coinside with the pH of the
surrounding media. I may be wrong, but it sure does sound like a logical
conclusion.
Lief Sorensen
HP Fort Collins, CO
Uucp ...!hpfcla!liefward@hao.UUCP (Mike Ward) (04/25/85)
> > I am curious as to what the latest and greatest evolutionary stand is on > "Spontaneous Generation". The stand of every modern scientist is that spontaneous generation is a thoroughly discredited notion. The rest of this posting by Lief seems to be arguing about some other theory.