‘SpudCell’ marks a significant breakthrough in synthetic biology, described as a pioneering synthetic cell system constructed from abiotic components capable of completing the cell cycle. While it’s an extraordinary achievement, it’s essential to clarify that this creation may not qualify as a living cell. SpudCell contains 36 genes that enable basic DNA replication but relies heavily on external assistance to function, failing after about five divisions. Nonetheless, this represents a monumental advancement in bioengineering, unrivaled by previous efforts.

Leading researcher Kate Adamala and her team at the University of Minnesota are making SpudCell an open-source project, encouraging future developments and collaboration. Here are the key details:

What is a SpudCell?

SpudCell represents a pivotal step towards the creation of microscopic life forms with fully understood functionalities. Prior endeavors in synthetic biology involved gene deletion in bacterial cells with limited genomes. For instance, researchers worked with a bacterium that originally had 901 genes, reducing it to just 493. In contrast, Adamala’s team focused on a minimalist approach, starting with a mere 36 genes. These genes mainly originate from Escherichia coli, along with fragments from phage viruses that infect bacteria and fluorescent proteins derived from jellyfish, which facilitate cell visualization.

Are SpudCells Alive?

SpudCells exhibit some cellular functions such as gene replication and division, albeit imperfectly. They require significant external support to perform these tasks. While researchers have induced evolutionary changes by introducing beneficial mutations, this process wasn’t spontaneous; it necessitated deliberate intervention. Kate Adamala notes, “If it can reproduce indefinitely and Darwinian evolution is possible, I would consider it living.”

Can We Call Them Synthetic Cells?

The classification of SpudCells as synthetic cells hinges on your definition. They are indeed assembled in a laboratory and perform various cellular functions, but they are not fully created from scratch. Instead, they incorporate components from existing cells, primarily those 36 genes. In essence, they represent a streamlined version of Escherichia coli, augmented with other cellular elements.

How Are SpudCells Assembled?

The research team engineered the 36 genes into seven circular DNA fragments. Numerous copies were produced and introduced into a solution containing essential cell components, including DNA, protein building blocks, and fatty molecules that spontaneously create cell-like bubbles. Some bubbles effectively housed all seven genomic sections.

The survival of SpudCells depends on two genes that code for proteins, forming membrane pores that allow the entry of small molecules. Larger molecules are supplied via small bubbles that merge with the SpudCells. Consequently, SpudCells cannot independently produce all necessary life-building components; they require external provisions.

How Do SpudCells Divide?

To achieve cell division, researchers added a large protein that interacts with one membrane protein, prompting collisions for space. This collision induces membrane distortion, leading some SpudCells to bud off and form new bubbles. However, this process doesn’t result in equal partitioning, and the “daughter” cells randomly inherit fragments of DNA, meaning many progeny lack a full genomic complement.

Why Not Consolidate All Genes into One DNA Piece?

While consolidating all genes could ensure complete inheritance by daughter cells, Adamala explains that working with large DNA fragments presents significant challenges. “Once a satisfactory genome is established, it typically needs to follow a single substantial genome piece.”

Why Do SpudCells Stop Functioning After Approximately Five Divisions?

The precise reason remains unclear, but SpudCells lack the capability to manufacture their own protein factories, or ribosomes, and require external supplies. “We suspect ribosome malfunction could be the reason cells cease to divide,” Adamala states. “If SpudCells could produce their own ribosomes, continuous division might be achievable, which is a goal for the near future.”

What is the Purpose Behind Creating SpudCell?

Adamala envisions a future where living biology is harnessed to produce essential petrochemicals, paving the way for reduced reliance on fossil fuels, along with significant climate and social benefits. Today, many vital chemicals, from plastics to pesticides, originate from oil and gas, which are not only harmful but also detrimental to normal cells. In contrast, synthetic cells could be engineered for better resilience against such toxicity.

Could SpudCells Be Dangerous?

Rest assured, SpudCells are comparably benign, likened to a dormant version of Frankenstein’s monster that requires constant nourishment. There’s minimal risk of spontaneous self-replication. Even if they were to attain full life capabilities, it is unlikely they would survive outside laboratory or factory settings, making existing bacteria a far more significant threat.