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Perhaps molecules in chemistry can take turns at scrabble more often than once a year: say once a second. How many seconds old is the universe then? It is 4.72 x1017 seconds old so we still have a problem because we need 20275 seconds to produce our gene product. The universe clearly doesn't have enough seconds to try out even a tiny fraction of the 20275 possible permutaions needed to make permease.
One way to reduce the problem is to take account of the natural redundancy in protein structures where proteins can tolerate a degree of sequence change in non-critical parts of the structure as long as the overall shape of the protein is maintained. If, for arguments sake, we accept that on average there are not one, but lets say 2 [see box 1] possible amino acids that could fit at every position in the protein, then the search is not for a single unique protein sequence but for any one of several functional variants where the probability of a functional amino acid at each position is reduced from 1/20 to 2/20, which brings the overall probability of gaining a functional permease down to 10275.This still barely dents the problem though [see box 2] .
The problem does not end here because information needs to be stored and translated in a physical medium. A gene is no use unless it does something, just as an architect's plan is no use without a builder. The builder of proteins in a living cell is a machine called the ribosome. It translates the genetic information into a sequence of amino acids adding 3-5 amino acids per second. The ribosome, even in the simplest bacterial cells, is made of 3 molecules of nucleic acid called rRNA and over 50 different proteins: it is a whole factory and exemplifies the true complexity of even the simplest life forms. All these proteins and amino acids need to be in place before the amazing information of a gene can be translated into a functional product, which leads us to a chicken and egg paradox because all these ribosomal proteins are coded for in the genes of the cell and of course they themselves need to be translated in order to make the translational machine we call the ribosome.
Furthermore, other molecules are essential to the functioning of the ribosome. The most significant of these is transfer RNA (tRNA) that functions as an adaptor converting the information on the DNA code to amino acids. Each amino acid has at least one specific adapter tRNA that picks it up and places it in position over the genetic code to which it corresponds. In addition, a series of other proteins control the working of the ribosome and last but not least the factory needs energy and that comes from a complex series of metabolic reactions. These reactions break down glucose and other simple fuel molecules into useable energy for the cell by a complex series of carefully controlled reactions. Even the entry of glucose into the cell, for metabolism, is controlled. That brings us back to our original molecule of permease that contains amino acids arranged in just one out of 20275 permutations.
The living cell, even the simplest cell, is actually very complex; far from a simple blob of protoplasm or a sac containing organic chemicals. Far away indeed from such an over simplified conception. Even the simplest cell known to man, the cell with the fewest genes,a sexually transmitted infection called Mycoplasma genitalium, has 477 genes. It is a parasite causing non-gonoccocal urethritis, and with so few genes (relatively speaking) of its own relies upon the genes of its unfortunate host for survival. Even it, then, is not an independent life form: it lives by virtue of association with another life form.
The apparent simplicity of a single cell, compared to a human body with trillions of cells, is likewise only a relative simplicity. Francis crick, the co-discoverer of the structure of DNA, marking the beginning of the genetic revolution, was astute in observing that: "The origin of life appears to be almost a miracle, so many are the conditions which would have had to be satisfied to get it going." He would, however, take great pains to distance himself from those who doubt the 'fact' of evolution. Scientific orthodoxy does not accept any challenge to the theory of evolution, perhaps as a reaction to the initial opposition of the European churches to any challenges to religious orthodoxy.
Today we witness an odd role reversal. The recent tsunami was enough to make the current archbishop of Canterbury seem to express a doubt in the existence of God. One wonders if any calamity great enough could strike the shores of scientific orthodoxy and cause the believers in spontaneous generation of life from raw chemistry to express similar doubts.
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