Extraterrestrial Sugar Found In Meteorites; Clue To Life’s Origins?

| Published: Thursday, November 21, 2019, 10:52 [IST]

Meteorites containing sugar was excavated by a team of international scientists. The extraterrestrial sugar adds to the hypothesis that chemical reactions in asteroids can make some unique ingredients in outer space. If proved right, it could further build evidence that a meteorite crashed on Earth billions of years ago, which assisted in the origin of life here.

Extraterrestrial Sugar Found In Meteorites

So far, "other important building blocks of life have been found in meteorites previously, including amino acids (components of proteins) and nucleobases (components of DNA and RNA)," said Yoshihiro Furukawa of Tohoku University, Japan, the lead author of the study. However, until now, sugar was one component that was missing.

The research study, published in the Proceedings of the National Academy of Sciences, provides the first direct evidence of extraterrestrial sugar found in meteorites. The team discovered ribose, arabinose and xylose in two different meteorites, NWA 801 and Murchison, which are rich in carbon. Furukawa says that this extraterrestrial ribose might have led to the formation of RNA on the prehistoric Earth, leading to the origin of life.

One might wonder why is ribose so important. Ribose is the crucial component of our RNA, which serves as a messenger molecule that copies genetic instructions from our DNA molecule and delivers it to the production factories within the cells. In a gist, the RNA is crucial to building specific proteins to carry out life processes.

Extraterrestrial Sugar: Source Of Life

The newly discovered extraterrestrial sugar throws light on the possibility that RNA coordinated life origins before DNA. Danny Glavin, the co-author of the research study at NASA's Goddard says that the sugar components in DNA were not detected in any of the meteorites. "This is important since there could have been a delivery bias of extraterrestrial ribose to the early Earth which is consistent with the hypothesis that RNA evolved first," he said.

The research team analyzed the powdered samples of the meteorites using a technique with gas chromatography-mass spectrometry, which sorts and identifies molecules by the mass and electric charge. The team is now considering the possibility that the extraterrestrial sugar found in the meteorites could have come from contamination by terrestrial life.