Information Technology Reference
In-Depth Information
Life is a paradoxical phenomenon which evolves for solving paradoxes. In fact,
the solutions it finds raise other paradoxes, which move the intrinsic mystery of its
nature forward.
Almost the totality of biochemical reactions is performed by means of specific
catalysts. They are bio-molecules which allow reactants to meet and to react in
the best way by decreasing the intensity of
activation energy
. These molecules are
called
enzymes
. Usually, each reaction needs its specific enzyme, which is often a
protein. However, this notion of enzyme immediately raises a very general problem
of logical nature. In fact, also enzymes are bio-molecules, therefore i) either they
need biochemical reactions producing them; therefore enzymes which in turn need
enzymes along a tautological regression, ii) or they need to be introduced into the
cell from outside. In the second case, either they are introduced in the cell in a free
way, or they need some specific molecules which select the kinds of molecules that
are allowed to enter. The case of nonselective introduction of enzymes is not rea-
sonable from many points of view, but basically it is biologically unreasonable that
in a cell any enzyme floating in the environment could enter.
In the case of a regulated introduction of enzymes, the problem of enzyme pro-
duction is only shifted to the problem of enzyme introduction. In fact, enzymes
should need specific biomolecules that are able to recognize them, by allowing them
to enter in the cell. But where do these introduction enzymes come from? In con-
clusion, enzymes are supposedly produced internally in the cell, but this assumption
implies a
petitio principii
. In fact, any reaction which synthesizes an enzyme pos-
tulates an enzyme too, therefore any chain of enzymes (A making B making C,
and so on, for a finite number of steps) needs a starting enzyme which cannot be
produced internally by the cell. In conclusion, some enzymes need to come from
outside, but this seems only to change the terms of the problem without solving it.
Therefore, where and how are enzymes produced/introduced in the cell? We call
this contradictory situation the
enzymatic paradox
.
A possible solution of the enzymatic paradox is the existence of molecules of a
kind that allows the synthesis of enzymes, but which are not enzymes and which
came from the outside. Where do they come from? Let us call these bio-molecules
I-molecules
for their intrinsic informational role. They came into the cell from out-
side, but their externality is in a temporal sense rather than in a spatial sense. They
are passed to the cell by its mother cell. Simple arguments of reliability imply that a
unique I-molecule collecting the whole information for the synthesis of all enzymes
is the best solution of the enzyme puzzle. But this unique I-molecule can be passed
to the daughter cell, after a duplication of it, otherwise the mother cell has to die as
soon as its unique copy of the I-molecule is released outside it.
The enzymatic paradox, and its solution outlined above, constitutes a sort of a
logical proof
of the necessity of the two levels in the organization cells: the M-level
of metabolism and the I-level for storing the information of enzyme construction.
According to this perspective, it turns out that metabolism and replication are two in-
tertwined phenomena, and the argument here outlined represents a
more geometrico
deduction of the dualism genes and proteins as a logical necessity of the autocat-
alytic nature of the biochemical reactions hosted in the cells. The following list of
