Will creating artificial life help us understand life in the universe?

It sure will. It will help us understand the chemical pathways that allow life to emerge on a planet, and to understand what the minimum requirements for a living system are so that we can identify its traces in our data. A spectacular experiment announced in 1999 by Dr. Clyde A. Hutchison III, at the University of North Carolina and his colleagues at The Institute for Genomic Research (TIGR), found that roughly a third of the genes in the disease-causing Mycoplasma genitalium were unnecessary for the bacterium’s survival. It normally has 517 genes, the smallest known, but they could get the bacterium to work with only about 265 to 350 genes. A continuation of this experiment was announced in November 2002, and is being funded at TIGR by the Department of Energy. One of the first genes they'll delete is the one that gives Mycoplasma genitalium the ability to adhere to human cells.

Many of the 200 genes to be deleted make it possible for the organism to survive in a hostile environment. The end result will be a delicate creature that survives only in a laboratory petri dish. But can we create a living organism with only 100 genes? How about 50? In a separate set of experiments using compounds present in interstellar clouds, astronomer Jason Dworkin and his colleagues at the NASA Ames Research Center created an organic goo that contained small cell-like vesicles. They used a vacuum into which 100 parts of water, 50 parts methanol, 50 parts ammonia, and one part carbon monoxide were added. As ultraviolet light shined on the mixture, it was cooled to a mere 15 degrees Kelvin for two days, then allowed to warm to room temperature for another two days. This was repeated for a month and the result was a black deposit containing a number of complex molecules and small round blobs that look amazingly like little cells.

Further analysis showed that these were thin walls of lipid molecules identical to cell membranes. Most living organisms squander dozens of genes to create such membranes themselves. Here you get them free of charge. Somewhere between these two experiments it is hoped we will eventually capture the step-by-step process that turns inorganic materials into self-replicating systems.

This answer was updated in 2011. See my books: The Astronomy Cafe (1998) and Back to the Astronomy Cafe (2003) for more FAQs in printed form. Author: Dr. Sten Odenwald, Copyright 2011

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