1 Comment

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  Stuart Ballard - 14 years ago

  This work is very encouraging, but claiming that a synthetic organism has been made entirely from man-made parts is simply false. All we have accomplished is the manufacture of a synthetic genome, which has been injected into a cellular envelope made the old fashioned way: bacterial metabolism. We may have enormous creative power of genetics, but metabolism and physiology have yet to be conquered. This is tantamount to saying we've invented writing when we've invented spoken language. We have the code, and can manipulate it and create it, but we lack the biochemistry to transform that code into more biochemistry, to allow for metabolism, to allow for physiology, to allow for total self generation. So we can speak, but we don't even know how we could turn our words into pictures that would last beyond their utterance. We just steal the interpretative machinery that other code has generated, so we are still using a biological product to construct this. It is thus NOT "entirely man-made," words which I've seen in many news reports.

  Perhaps some day we will mix up some DNA, a bunch of synthetic phospholipids, a few hundred or thousand different small molecules, maybe a perfectly tuned mixture of short polynucleotides and polypeptides that will autocatalytically convert into ribosomes and RNA polymerase, all put through some mechano-chemical process causing the mixture to nucleate into bi-layer lipid membranes surrounding dense globs of biomolecules. My bet: even if you got all these parts together, you would not have enough time to achieve a critical mass of metabolic components in any given quasi-cell to start autonomous replication. Life emerged when this sort of mixture (with far fewer constraints if you believe the RNA world hypothesis) was held in this state for a long time in enormous volume.