Glycine's eight forms swap via quantum tunnelling even at 10 Kelvin.

Scientists want to find glycine, a simple amino acid that builds proteins on Earth, in deep space. Space rocks like meteorites, comets, and asteroids carry glycine, but past searches in the interstellar mediuminterstellar mediumThe gas and dust that fills the space between stars. have failed. Glycine can twist into eight different shapes, known as conformations. This study investigates how glycine flips between these shapes in the dark. At temperatures from 300 K down to 10 K, these shape changes happen through quantum mechanical tunnellingquantum mechanical tunnellingA quantum effect where particles pass through energy barriers they classically could not cross., where molecules pass through energy barriers instead of climbing over them. The researchers computed the rates of these shape shifts to understand which forms appear most often. Using these speeds, they provide recommendations to maximise the chances of finally detecting glycine in space.

Why it matters

Astronomers have searched for glycine in space for decades without success. This work shows that glycine's shape-shifting between eight forms happens via quantum tunnelling even in the cold vacuum of space. Knowing these rates tells scientists which forms to look for and when, increasing the chance of finally detecting this key building block of life.

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