One of the great mysteries of science is the origin of life on Earth. This fundamental question begins with the transition of inorganic molecules into organic matter.
Scientists including one of our Bilkent University Faculty of Science graduates, S. Furkan Öztürk (PHYS’18), now made a series of breakthrough discoveries on this subject. “It is a real breakthrough” says origin of life chemist and Nobel laureate Jack Szostak, “Homochirality is essential to get biology started, and this is a possible – and I would say very likely – solution.” (https://www.science.org/content/article/breakthrough-could-explain-why-life-molecules-are-left-or-right-handed).
Biologically important molecules like amino acids and sugars are chiral, namely they can exist in mirror-symmetrical pairs. Yet biological systems are homochiral, life selectively uses left-handed amino acids and right-handed sugars. Single handedness of biomolecules—named biological homochirality—is one of the biggest problems in science, as listed among 125 important questions in natural sciences by the Science magazine in 2005.
After completing his undergraduate education at Bilkent Department of Physics, S. Furkan Ozturk went on to pursue a PhD degree at Harvard University. His studies suggest a plausible solution to this elusive problem. In a quest of three articles, the authors combine state-of-the-art knowledge in physics, prebiotic chemistry, and geochemistry and offer a physical mechanism that can break the mirror symmetry of biomolecules under prebiotic Earth conditions.
The mechanism they offer is based on a recent discovery in chemical physics named the chiral-induced spin selectivity (CISS) effect, which established a strong coupling between the electron spin and molecular chirality. To manifest this phenomenon, the authors utilize magnetic mineral surfaces, like magnetite, as chiral entities and break the chiral symmetry of an organic molecule that is central to the synthesis of RNA. Their results provide a plausible pathway to obtain homochiral RNA under prebiotic conditions.
- Ozturk, S. Furkan, et al. “Origin of biological homochirality by crystallization of an RNA precursor on a magnetic surface.” Science Advances23 (2023): eadg8274.
- Ozturk, S. Furkan, et al. “Chirality-Induced Magnetization of Magnetite by an RNA Precursor.” arXiv preprint arXiv:2304.09095(2023).
- Ozturk, S. Furkan, Dimitar D. Sasselov, and John D. Sutherland. “The central dogma of biological homochirality: How does chiral information propagate in a prebiotic network?.” arXiv preprint arXiv:2306.01803(2023).