European scientists have started work on a project to create simple forms of life from scratch in the lab, capitalising on theoretical and experimental advances in the fast-growing field of synthetic biology.
Starting with inanimate chemicals, the researchers aim to produce metabolically active cells that grow, divide and show “Darwinian evolution” within six years.
The €13mn “MiniLife” project, which is funded by the European Research Council and involves biologists and chemists from several universities, could be the first in the world to reach the minimum criteria for a synthetic living system.
“Success would constitute a landmark achievement in basic science,” said Eörs Szathmáry, director of the Centre for the Conceptual Foundations of Science at the Parmenides Foundation in Germany, who is a principal investigator on the ERC grant. “De-novo creation of living systems is a long-standing dream of humanity.”
John Sutherland, who works on the chemistry of early life at the MRC Laboratory of Molecular Biology in Cambridge, said the project joins a growing worldwide effort to “create minimal living systems”.
Sutherland, who is not involved in the MiniLife project, added: “This is driven by the perennial desire to understand how life originated on Earth and whether it could also have originated elsewhere in the observable universe.”
Other artificial life researchers are working with the known building blocks of life on Earth, particularly the nucleotides that make up ribonucleic acid. The ERC project, in contrast, aims truly to start from scratch, without using molecules that are themselves products of evolution.
“We abstract away from known life forms because they are highly evolved creatures,” said Szathmáry, “and simplify so as to arrive at a minimalistic formulation.”
The MiniLife researchers are evaluating four systems that might, individually, or in combination, be developed into a basis for minimal life. All are “autocatalytic”, a property essential for self-replication in which a chemical reaction is catalysed by its own products.
One candidate is the formose reaction. The process, discovered in the 19th century, converts an extremely simple chemical, formaldehyde, into an increasingly diverse and complex series of sugar molecules. As the reaction is fed with formaldehyde, the droplets’ behaviour varies with the composition of sugars inside them.
“Some grow faster and divide more quickly than others,” said Andrew Griffiths, a MiniLife investigator at the École Supérieure de Physique et de Chimie Industrielles in Paris. “We end up with the emergence of something equivalent to fitness in biology, like a mixture of slow-growing and fast-growing bacteria, but in a very simple chemical system.”
The formose-based system must be able to display reliable hereditability — passing on acquired characteristics from one generation to the next — perhaps in conjunction with one of the other systems being evaluated.
The six-year timing is ambitious, said Griffiths, who is optimistic that the project will be able to “demonstrate rudimentary Darwinian evolution”. As a minimum that would involve a system that can switch between two heritable states in different environments, analogous to the famous peppered moth whose wings are white in clean environments and black when it lives in polluted places with dark surfaces.
Sijbren Otto, a professor of systems chemistry at Groningen university and another member of the MiniLife team, said his primary motivation was “fascination with the nature and origin of life. Although the molecules we develop will probably not be the ones from which life started on the prebiotic Earth 3.8bn years ago, the mechanisms we hope to unveil will be very relevant for understanding what happened then.”
Last month an international group of researchers warned of the “unprecedented risks” posed by another area of synthetic biology. They said “mirror life” — manufactured bacteria that are structural reflections of natural microbes — could overwhelm the defences of people, other animals and plants.
Asked about the safety of the MiniLife project, Otto said its creations were “extremely unlikely to have any viability outside very controlled lab conditions” and posed no possible risk to the public.
However, the team is working with experts to develop an ethical framework for the research. “Now is the time to think much further ahead to where the research is likely to lead,” Otto said.
