Origin of life on Earth: Cyanide may have been the key ingredient

(Representational image)

New Delhi: Researchers have come across a strange finding that may explain the origin of life on early Earth – cyanide.

The beginning and the consequent evolution of life on Earth has been under constant scrutiny in the field of science.

In November 2017, a team of researchers from The Scripps Research Institute (TSRI) in the US hypothesized that a chemical reaction called phosphorylation may have been crucial for the assembly of three key ingredients in early life forms.

Now, the study has found that a mixture of cyanide and copper, when irradiated with ultraviolet (UV) light, may have produced simple sugars that formed a key ingredient responsible for the origin of life on Earth.

"One story for the origin of life is what we call the RNA world," said Zoe Todd from the Harvard University in the US.

"In order to make something like an RNA nucleotide, you need these sugars. This shows that process was plausible on the early Earth," said Todd, a researcher in the study published in the journal Royal Society of Chemistry.

When scientists in the UK demonstrated that the system could produce simple sugars such as glycolaldehyde and glyceraldehyde in 2012, it became a key step in showing that the hypothesis was plausible.

Those tests were performed under ideal conditions – with relatively high concentrations of both cyanide and copper, and powerful lamps that generated high-energy, 254-nanometer wavelength light.

However, previous research has shown that early Earth would have experienced a range of wavelengths shorter than typical on the planet's surface today.

Todd and Dimitar Sasselov, a professor at Harvard, set out to test the system under those conditions.

They combined small amounts of cyanide and copper in an airtight quartz container and then hit the solution with lower-intensity light from tunable xenon lamps.

Using prisms, Todd was able to separate the light into different wavelengths and target the system with a specific wavelength for hours at a time before running tests to confirm the reaction was actually taking place.

By adjusting the system based on specific conditions – which molecules are present in an atmosphere and intensity of the UV light produced by nearby stars – researchers could use the system to model whether the reaction could operate on other planets, Todd said.

(With PTI inputs)