SpudCell: First Artificial Cell With a Complete Life Cycle Created

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A group of scientists in a Minnesota laboratory have made history, creating the first artificial cell with a complete life cycle. SpudCell, as the team behind it has dubbed the creation, is built entirely from known chemical components, and can grow, replicate its genome, divide into new generations of cells, and even demonstrate natural selection and competition as its genes change. That’s not to say SpudCells are alive, mind you, as the team behind it aren’t claiming to have become gods. What they have done, they note in a preprint paper [PDF] published while awaiting peer review, is to give new insights into the minimal qualifications for what it actually takes for something to be alive. That, and they’ve created what they say could be a “chassis” that could be adapted for everything from formulating new drugs to the actual creation of artificial organisms. “SpudCell is not a ‘finished’ cell, and it is far simpler than anything in nature,” biochemist, University of Minnesota professor, and SpudCell project leader Kate Adamala told The Register in an email. “SpudCell is proof of what is possible. It proves that non-living, defined molecules can be assembled into a cell capable of functions that previously were exclusively reserved for natural life.” For those wondering where the name came from, Adamala told us that it was originally dubbed “Potato Cell” as a nod to her Polish heritage, before the name was shortened to SpudCell. In terms of those minimal qualifications, one of the things that SpudCell suggested was how few kilobase pairs (kbp - one kbp represents 1,000 base pairs) a genome may need to support a complete synthetic cell cycle. Prior scientific work estimated a minimal genome could be as small as 113 kbp (human genomes contain around 3 million kbp), but SpudCells only contain 90 kbp. SpudCells are also able to divide without the need for a cytoskeleton, the internal scaffolding that gives many cells their structure and helps coordinate cell division, side-stepping what the team said has long been a bottleneck in synthetic cell research due to the cytoskeleton's complexity. Instead, SpudCells divide when proteins used to grow the cell crowd together at the membrane surface of the cell until mechanical stress forces it to split. As mentioned above, SpudCells also demonstrate competition and natural - or unnatural, in this case - selection. “When researchers introduced a genetic change that increased production of the fusion protein, cells with that change grew faster and produced more offspring,” the team explained. “After five generations, the faster-growing variant had outcompeted the original.” As a rather primitive cell without the full complement of features needed to sustain life, SpudCell does have its limitations. “SpudCell has a very primitive metabolism, and it cannot yet build its own ribosomes,” Adamala told us. Because SpudCells can't yet build their own ribosomes, researchers have to keep 'em fed with liposomes carrying ribosomes, enzymes, lipids, and other molecular components needed to keep the synthetic cells functioning. That’s good news for anyone worried about the little creatures escaping the lab and wreaking havoc on the outside world: Their biology precludes survival outside very specific lab conditions. The artificial cellular future The potential uses of things like SpudCell, which is in essence an artificial proto life form with biology that’s entirely known, understandable, and manipulable, are vast. As Adamala explained it to us, medicines, materials, industrial chemicals, and other manufactured products the world relies on are created via molecular transformation in natural living cells we manipulate to produce desired products, or from industrial processes with huge energy and environmental costs. “Cells built from scratch could perform molecular transformations industrial chemistry cannot,” the biochemist told us. Using biology in such a way requires far more understanding of cellular structures and processes, Adamala added, and to do that we need cells we fully understand - like SpudCell. “I’m a chemist, and ever since I started working on biology, I’ve been frustrated by our inability to fully describe and characterize any natural living cell,” Adamala said. “To understand and routinely use biology, we need engineerable and fully defined cells.” That’s where the second part of her team’s work comes in: Together with a group of colleagues, Adamala is taking her work out of the university lab and into a public-benefit institution called Biotic. The outfit intends to do its work publicly and openly in a bid to standardize artificial cell research and speed up whatever societal benefits the project could help create. “Every lab in this field is solving the same problems from scratch, and little of that institutional knowledge is carrying over to the next group,” Adamala explained in an email. “That is the problem I want Biotic to solve: How to turn a field of one-off accomplishments into a real engineering discipline, built on shared, open foundations, so the ability to engineer biology is not something only a few private hands ever hold.” There’s a lot of work to be done before SpudCell takes Biotic and the artificial cell research world beyond the basics, but it’s a start that SpudCell has contributed to, Adamala said, making a number of long-standing challenges tractable instead of far-future dreams of labcoat-bedecked boffins. “My personal immediate to-do list includes ribogenesis, better metabolism, and more robust division,” the professor told us. “Those three things, with the support of the community built by Biotic, will go very far towards making it a viable platform for practical applications.” ®