Tokyo, Oct. 11 (Jiji Press)–An experiment by French chemist and microbiologist Louis Pasteur in the mid-19th century had inspired 2026 Nobel Prize in Chemistry winner Kenso Soai’s research. Discovering a reaction known as the “Soai reaction,” the 76-year-old Japanese chemist, who is a professor emeritus at Tokyo University of Science, has worked to unravel the mystery of why substances such as amino acids and sugars favor one of the two mirror-image forms over the other. The discovery of nonlinear effects and autocatalysis in asymmetric organic synthesis, as cited by the Royal Swedish Academy of Sciences as the reason for Soai’s Nobel prize, is part of this area called chiral chemistry. At a press conference held Wednesday after he was named a Nobel Prize in Chemistry co-winner for this year, Soai said that during a visit to the Institut Pasteur in Paris, he “was quietly impressed personally” by crystals in a small box that may have been used by Pasteur. Chirality is a property in which objects or molecules look identical to their mirror image but cannot be stacked on top of one another, just like a person’s right and left hands. In the first half of the 19th century, it was discovered that light passing through a crystal could exhibit right or left optical rotation and that this is caused by differences in crystal structure. Such optical rotation is also observed in cane sugar and tartar found in wines. In 1848, Pasteur observed optical rotation in a sodium ammonium tartrate solution and discovered that the difference stemmed from the chirality of the molecules themselves. He then dedicated his research on why living organisms produce only one of the two mirror-image isomers, examining factors like sunlight directions and the effects of magnetic fields. He, however, could not yield conclusive results. After a long time, Soai revisited this longstanding question, demonstrating that an asymmetric autocatalytic reaction can occur, in which only one of the two mirror-image isomers acts as a catalyst to overwhelmingly amplify itself. As self-replication is a defining characteristic of life, Soai said that it is “a very convenient system (for organisms) to last for a long time.” END [Copyright The Jiji Press, Ltd.]
