The American Crystallographic Association joins the international scientific community in mourning the passing of Professor Ada Yonath, Nobel laureate and pioneering structural biologist, who died on August 31, 2026, at the age of 87.

Professor Yonath transformed our understanding of the ribosome—the complex molecular machinery responsible for translating genetic information into proteins. When she began studying ribosomes in the late 1970s, many scientists believed these large and unstable structures could not be crystallized. Undeterred by widespread skepticism, she pursued the challenge with remarkable courage and perseverance. After years of work and thousands of attempts, her research helped reveal the ribosome’s three-dimensional structure at the atomic level.

Her discoveries also provided critical insight into how antibiotics bind to bacterial ribosomes, how those drugs prevent bacteria from producing essential proteins, and how antibiotic resistance develops. This work continues to inform efforts to improve existing treatments and develop new antibiotics.

Professor Yonath shared the 2009 Nobel Prize in Chemistry with Thomas Steitz and Venkatraman Ramakrishnan for studies of the structure and function of the ribosome. In its Winter 2009 issue of RefleXions, the ACA described how the three scientists came from different backgrounds and followed different scientific paths that ultimately converged in the effort to map the ribosome. The article also recognized the many other researchers whose work contributed to this historic achievement.

Born in Jerusalem in 1939, Professor Yonath earned her PhD in X-ray crystallography from the Weizmann Institute of Science and later established Israel’s first protein crystallography laboratory. She remained actively engaged in research, publishing, and scientific collaboration until the final days of her life.

Professor Yonath’s legacy reaches far beyond her many honors. She showed generations of scientists what can be accomplished through curiosity, imagination, and the determination to pursue questions others consider impossible.

The ACA extends its deepest condolences to Professor Yonath’s family, colleagues, students, and the Weizmann Institute community. We join crystallographers around the world in honoring her extraordinary life and enduring contributions to science.