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Not sure you guys have seen or talked about this already, but I just got on-line access to New Scientist Magazine. The Feb 12 2005 issue was about creating artificial life. Here's a short summary about a Los Alamos team's attempt to do so:
The key difference between life and non-life is Darwinian evolution. This requires some sort of device, a molecule for example, to carry hereditary information. The device must have a separate identity from it's environment, that is, must be contained in some sort of container, and finally, must have an energy source: a metabolism. Thus we have the most fundamental definition of life: heredity, containment, metabolism. The Los Alamos group is attempting to simulate these three as follows:
Containment: In a word fatty-acids. You know, polar on one end, non-polar on the other. Just like real cell membranes. These form "vesicles" naturally.
Heredity: They're using PNA (peptide nucleic acids). Instead of ribose-phosphate backbone like DNA, these have protein chains to which nucleic acids are attached.
Metabolism: I quote: "The Bug will also be supplied with inactive PNA precursors bound to a photosensitive molecule. . . . when light strikes this photosensitiser, it breaks off to release the active PNA fragment."
Don't quite understand how that supplies energy at least along the lines of glycolysis, Kreb cycle, ATP synthesis, etc.
Anyway, if you're interested in prebiotic evolution, you may wish to check out this issue.
The key difference between life and non-life is Darwinian evolution. This requires some sort of device, a molecule for example, to carry hereditary information. The device must have a separate identity from it's environment, that is, must be contained in some sort of container, and finally, must have an energy source: a metabolism. Thus we have the most fundamental definition of life: heredity, containment, metabolism. The Los Alamos group is attempting to simulate these three as follows:
Containment: In a word fatty-acids. You know, polar on one end, non-polar on the other. Just like real cell membranes. These form "vesicles" naturally.
Heredity: They're using PNA (peptide nucleic acids). Instead of ribose-phosphate backbone like DNA, these have protein chains to which nucleic acids are attached.
Metabolism: I quote: "The Bug will also be supplied with inactive PNA precursors bound to a photosensitive molecule. . . . when light strikes this photosensitiser, it breaks off to release the active PNA fragment."
Don't quite understand how that supplies energy at least along the lines of glycolysis, Kreb cycle, ATP synthesis, etc.
Anyway, if you're interested in prebiotic evolution, you may wish to check out this issue.