"But if biomolecules can be made by non-biological systems then they are
misnamed are they not? I propose that your definitions contain a lurking and
subtle vitalism."
Not really, but part of your confusion stems from the fact that in this kind
of situation we are hampered by the lack of a proper and precise terminology
(at least until we can agree on one). Biochemically speaking, a biomolecule
is an organic molecule used exclusively in biological systems. How they are
made is irrelevant; a cell will respond the same to an enzyme made by an
automated organic synthesizer (in other words synthetically using a chemical
industrial method) or made in a gene expression system (in other words
naturally using a biotechnology method), assuming of course that the enzyme
is active. What you are suggesting to be vitalism is simply the
biomolecule's chemistry. In other words, my definitions are based on the
recognition that what makes a biomolecule biologically active is its
chemical nature. This has been proven time and again by all the drugs
manufactured by organic industrial processes, whose structures do not
resemble any biomolecule, but whose chemistries imitate the chemistries of
specific biomolecules. This wouldn't happen if I was implying any sort of
vitalism.
Besides, it seems to me that it is you who is (subconsciously) advocating
vitalism by your objection to the claim that biomolecules can be made by
non-biological systems. This is reminiscent of the old controversy over
whether biomolecules could be made by organic synthesis in a laboratory,
which was resolved over 170 years ago. At the beginning of the last
century, biochemistry was barely a recognized science and still very much
the domain of biologists. At the time, vitalism was a strong belief among
many scientists, including many biochemists. These scientists claimed that
biomolecules could only be made in biological systems, because vitalism was
needed to make them and they needed vitalism to be biologically active.
However, a growing minority advocated treating biomolecules just like
inorganic molecules, as chemical entities controlled by specific chemical
mechanisms. They advocated that it should be possible to make biomolecules
in a laboratory with the right setup. (In many ways, their controversy is
similar to the controversy we in this group are having over abiogenesis.)
The matter was not resolved until 1828. Friedrich Wohler -- co-discoverer
of isomerism, inventor of organic synthesis and one of the fathers of modern
organic chemistry -- stumbled upon the answer while studying the chemistry
of cyanic compounds. He discovered that if he mixed potassium cyanide with
ammonium sulfate he got urea, a biomolecule. According to vitalism that
should have been impossible; only biological systems could create urea. Yet
Wohler had shown how to do it without using any form of biological system
whatsoever. With that one experiment alone, vitalism lost its grip on
biochemistry and the discipline swung into the domain of the chemists.
Vitalist biologists tried to hang on by insisting that artificially made
biomolecules had no biological activity because they had no vitalism, but
non-vitalist biologists shot that down by demonstrating that animals given
artificial biomolecules reacted to them as if they were natural. From then
on, vitalism as an influence in biology was dead. Objections to the fact
that biomolecules can be made by non-biological methods sounds alot like
attempting to reintroduce vitalism to biochemistry.
In fact, Wohler's experiment is itself an abiogenetic event -- even by
Burgy's standards. It involves making "living matter" (urea) from
"non-living matter" (potassium cyanide and ammonium sulfate) using a
non-biological method (organic synthesis).
Kevin L. O'Brien