A single cell is the most awesomely sophisticated molecular machine yet produced. A self-directing, self-replicating micro-factory capable of complex constructions, automated repair and even (like all good sci-fi-sounding devices) self-destruct. The first cells, however, were much less "complex mechanisms" and significantly more "Shake and Bake" - a model that we're now ready to build ourselves.
These proto-cells didn't have any sophisticated cellular functions, consisting of nothing more than a fatty cell wall just dense enough to have an inside and an outside, with a speck of DNA on the "not-outside" side. This child's model of a cell drifted in the chemical soup that created it until the correct nucleotides were absorbed and allowed it to replicated the DNA.
If it sounds hideously unlikely, be aware that some Harvard researchers, including Harvard Medical School's Jack Szostak, have managed exactly that. Mixing some fatty acids and DNA in a test tube of water, they found that the lipid molecules formed a crude ring around the information-rich core. Even more strikingly, nucleotides added to the solution successfully entered the cell and replicated the DNA within a day. We can only hope the scientist took this chance to raise the test tube and cry "In my hand I hold the secret to LIFE ITSELF!", triggering dramatic lightning strikes and thunder in the background.
There are still a few tricks to work out, such as how the original ancestor cells successfully split in two without spilling their precious genetic cargo - but come on. These guys just replicated what took a planet and millions of years in a couple of terms with less than ten dollars of glassware. Awe and wonder are deeply subjective quantities, but I can say for a fact: if you are not impressed by this work, you are wrong.
Posted by Luke McKinney.
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