Excerpts from Kotulak’s article: Scientists now believe that it may be possible to create the first artificial unit of life in the next 5 to 10 years. “We’ve been saying that for the last 50 years,” notes researcher David W. Deamer. “What makes it different now is that we have a critical mass of people interested in the field and some recent breakthrough discoveries.”
Spearheading the drive is the European Union’s Programmable Artificial Cell Evolution project, recently established with a grant of about $9 million. This month PACE is scheduled to open the first institution devoted exclusively to creating artificial life, called the European Center for Living Technology, in Venice.
Researchers argue over the definition of life, but they generally agree that it must have three elements: a container, such as the membrane wall of a cell; metabolism, the ability to convert basic nutrients into a cell’s working parts; and genes, chemical instructions for building a cell that can be passed on to progeny and change as conditions change. Each of these critical elements has now been achieved in the laboratory, albeit in rudimentary form, and scientists say they are ready to try to put them all together in one working unit.
One of the tricks learned is how to use the remarkable properties of clay, thought to have been abundant on the early Earth. Clay has natural catalytic properties–it speeds up the assembly of lipid membranes a hundredfold, for example, and also hastens the assembly of genetic material called ribonucleic acid or RNA.
How the first genes got together is a big mystery. Many scientists believe that RNA may have preceded DNA because it can carry genetic instructions and, unlike DNA, make copies of itself. David Bartel of the Whitehead Institute for Biomedical Research is trying to make RNA that can fully reproduce itself. So far he has gotten compounds to assemble into small RNA sequences that can make partial copies of themselves.
Other forms of nucleic acids besides RNA and DNA may be the cornerstone of artificial life. Rasmussen of Los Alamos National Laboratory and Liaohai Chen of Argonne National Laboratory believe they have a good chance of making an artificial cell by using a slightly different version of DNA called polypeptide nucleic acid. Unlimited variations of PNA can easily be made. They love to stick to the surface of membranes where they can suck up nutrients and hopefully churn out all kinds of novel chemicals, including more cell membrane lipids. “We have all the pieces, and we have demonstrated that our metabolism can produce the container molecules,” Chen said. The protocells that assemble are 10 million times smaller than a bacterium, he said.
Physicist Norman Packard, who established the first company, ProtoLife, to capitalize on the new field of living technology, thinks of artificial cells as tiny machines that can be programmed to clean out arteries, deliver drugs to specific sites in the body and perform other jobs with great precision. “The goal of the company is to realize the vision of producing living artificial cells, and also producing other forms of living chemistry, and then programming them to do useful chemical applications,” he said. “The range of useful chemical functions we ultimately envision is vast.”