All life on earth, including your own, depends on a series of chemical reactions that require enzymes to catalyze or jump-start the process. Simply put, you couldn’t digest your food or make DNA without enzymes. Now, English researchers have made the world’s first synthetic enzymes, created from artificial molecules (not occurring in nature), yet still capable of triggering chemical reactions. Their research advances the field of synthetic biology while also providing a possible platform on which to base a new generation of drugs. It also may open our eyes to life on other planets.

“The creation of synthetic DNA, and now enzymes, from building blocks that don’t exist in nature also raises the possibility that, if there is life on other planets, it may have sprung up from an entirely different set of molecules, and it widens the possible number of planets that might be able to host life,” said Dr. Alex Taylor, the study’s first author and a research associate at St John’s College at Cambridge, in a press release.

Remind Me About Synthetic Biology

Even before Gregor Mendel conducted his experiments on pea plants and established rules of heredity, farmers had been cross-breeding plants and animals for generations as a way to establish the traits they found most desirable. Over time, scientists improved and enhanced these methods and eventually developed genetic engineering techniques to speed up the process of cultivating new breeds. Taking the general idea one step further, some scientists chose to use artificial ingredients, instead of those occurring in nature, to create new and improved breeds.

Today, then, it is possible to make entirely new sequences of DNA from scratch, and this has opened the door to entirely new organisms with entirely new traits. Essentially, scientists use computers and laboratory chemicals — instead of naturally occurring ingredients — to first create new sequences of DNA and then design previously unseen organisms. Synthetic biology, then, is the application of modern engineering principles to the fundamental components of biology.

Importantly, the current study, led by Dr. Philipp Holliger of the MRC Laboratory of Molecular Biology, advances this new science. In 2012, Holliger and his colleagues created six synthetic molecules, called XNAs, to mimic DNA and RNA in their ability to store genetic information and evolve through natural selection. Their latest work expands on this previous research by taking the XNAs, or unnatural building blocks, and creating four different types of synthetic enzymes.

The result is what they call XNAzymes.

XNAzymes, like enzymes, are capable of catalyzing simple reactions in a test tube. They can cut and join RNA strands in vitro, for instance, and one of them is capable of joining XNA strands together. According to the researchers, this represents one of the first steps to creating a living system.

“Our XNAs are chemically extremely robust and, because they do not occur in nature, they are not recognized by the body’s natural degrading enzymes,” said Holliger. The greater stability of the XNAzymes, Holliger and his colleagues believe, suggests they could be useful when developing new therapies for a range of diseases, including cancer and viruses. While life on another planet has yet to be discovered, Holliger’s work not only opens our eyes as to what that might look like but also enhances life on this planet in the meantime.

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