Using a novel approach, scientists have cast additional light on an age-old question: how did life originate on Earth? The research, which was conducted by an international team, provides a glimpse into the earliest processes responsible for the formation of life’s building elements.
It is believed that small puddles of water containing urea, an essential organic compound for nucleo base formation, were exposed to the intense high-energy radiation from space, which was ubiquitous before life was formed, causing the urea to undergo conversion into reaction products that eventually formed DNA and RNA.
To delve deeper into the mechanisms behind urea ionisation and reaction, as well as the pathways and energy dissipation involved, the international team, including corresponding author Zhong Yin, an associate professor at Tohoku University’s International Centre for Synchrotron Radiation Innovation Smart (SRIS), created a novel X-ray spectroscopy technique.
Utilising a light source of high-harmonic generation and a sub-micron liquid flat-jet, the new method enabled researchers to examine chemical reactions in liquids with unprecedented temporal precision. The team was able to observe the intricate alterations in urea molecules at the femtosecond level, which is equal to one quadrillionth of a second.
“We have demonstrated for the first time how urea molecules react when ionised. Radiation that causes ionisation damages the urea biomolecules. But in dissipating the energy from the radiation, the ureas undergo a dynamical process that occurs on a femtosecond time scale,” said corresponding author Zhong Yin, an associate professor at the International Centre for Synchrotron Radiation Innovation Smart (SRIS) at Tohoku University.
This new approach made it possible to investigate biochemical processes in an aqueous context, which closely resembles their natural habitat. The development of a device capable of producing an ultrathin liquid discharge, with a thickness of less than one millionth of a metre, within a vacuum was essential to the experiment. A thicker jet would have impeded measurements by absorbing a substantial amount of the X-rays used in the investigation.
Yin believes that their discovery not only sheds light on the origin of life on Earth, but also paves the way for new research avenues in the burgeoning field of attochemistry.
“To comprehend chemical reactions in real time and to push the boundaries of attochemistry, shorter light pulses are required. Yin stated that our method permits scientists to observe a molecular movie while following each stage of the process.
The novel X-ray spectroscopy method has the potential to revolutionise our understanding of the origins of fundamental biological processes.
The findings of the team are published in Nature.
