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Researchers claim they are closer to creating life from scratch after building tiny, quivering blobs that use lab-made DNA to feed, grow and multiply in a dish.

The synthetic cells were made from chemical compounds and are believed to be the first to demonstrate the complete cell cycle of growth, genetic replication and splitting to produce the next generation.

The work raises the prospect of artificial organisms that are designed and built to churn out drugs, foods, fuels and other materials. But it may also shed light on the profound question of how particular assemblies of inanimate matter cross a threshold to become life.

Dr Kate Adamala, who led the research at the University of Minnesota, said: “It is not as robust, as fast, or as good at most of its functions as a natural cell, but it is proof of principle that molecules can reconstitute behaviours that up until now we only associated with natural living cells. If we want to be able to engineer biology, we really have to understand exactly the blueprint, every component of it, so we know what we’re changing.”

Scientists have tried to make synthetic life for decades. In 2010, Craig Venter, the late genetics pioneer, built an organism based on a bacterium that causes mastitis in goats. Others have achieved similar feats.

Instead of modifying natural cells, Adamala’s team built SpudCells from the bottom up to ensure that every component was known and understood. They started with tiny water-filled spheres called liposomes which are a few thousandths of a millimetre wide and added a small amount of synthetic DNA to provide basic functions. Adamala calls them SpudCells to evoke Sputnik and the dawn of the space age, but it’s not the only reason. “I’m Polish,” she said. “I’m mostly made of potatoes.”

SpudCells work only in a liquid that is brimming with vital chemicals such as ATP, the main energy-carrying molecule that living cells manufacture from nutrients. To grow, SpudCells fuse with minuscule “feeder” liposomes in the liquid. These contain molecules, enzymes and microscopic structures called ribosomes the SpudCells need to make proteins. The SpudCell’s genome carries other instructions to copy its genome and divide.

To mimic the evolutionary concept of survival of the fittest, the researchers showed how SpudCells with a genetic growth advantage spread through the population, outcompeting original SpudCells. Prof Tom Ellis, at Imperial College London, said the work was probably the field’s “biggest breakthrough in recent times”.

“Making a synthetic cell helps us understand the exact minimum requirements for life and how life might have emerged from chemistry,” Ellis said. “It’s also useful as it provides a fully understood system for testing biological circuits and computer models of cellular life.”

Watching SpudCells divide was striking to witness, Adamala said. “They’re among the most beautiful images I’ve seen, but obviously I’m biased. To most people, looking at it under the microscope, it doesn’t look like much … It’s a blob.” SpudCells are not alive, but could become a chassis with which to build life, she added.

For Adamala, the work is proof of principle that synthetic cells can behave like living cells. But they are nowhere near as capable as living cells. SpudCells are completely reliant on the substances and components in the liquid in which they are immersed. They cannot build their own protein-making machinery, control their metabolism, or clear their waste. And when they divide, they often pass on the wrong amount of DNA. They conk out after a few generations.

Adamala and others are launching an institution called Biotic to pool global expertise and build SpudCells into something more impressive. The goal, according to the co-founder Prof Drew Endy, a bioengineer at Stanford University, is to build “an operating system for life” made from genes and biochemistry. The study has been released as a preprint, before peer review, so other labs can scrutinise the work without delay.

Prof John Dupré, a philosopher and founder of the Centre for the Study of Life Sciences at the University of Exeter, questioned the point of such synthetic cells and whether they would be more effective for making drugs, food, fuel and materials than modified bacterial cells. They may not tell us much about life, either, he added. “It will, perhaps, provide a compelling argument against those who think there is some immaterial substance in addition to the chemicals that breathes life into material stuff. But almost no scientist now believes this,” he said.

“What is missing, I think, is the relational aspect of life which has become clear in the growing realisation that life is almost universally symbiotic,” he added. “If synthetic cells are used only to produce valuable chemicals this relational aspect might be absent, but so would one of the most interesting aspects of actual living beings.”