Prof. Ada Yonath of the Weizmann Institute, who deciphered the structure of the ribosome and won the Nobel Prize in Chemistry in 2009, passed away on August 31, 2026. Over decades of research, she persisted with questions that were considered almost impossible, contributed to understanding the mechanism of action of antibiotics, and warned of the crisis of bacterial resistance. In interviews with the Haydan website over the years, she spoke about the unexpected path to science and the perseverance it took to reach the breakthrough.
Prof. Ada Yonath, bride Nobel prize Chemistry for 2009 and recipient of the Israel Prize, passed away today, August 31, 2026, at the age of 87. This was announced by Weizmann Institute Science, where she worked for most of her scientific life and where, according to the institute, she continued to run an active laboratory, publish research, and conduct scientific collaborations until her last days.
Yonath was one of the most prominent Israeli scientists in the world. Her main achievement was deciphering the structure and function of theribosome – The molecular machine in each cell translates genetic information into proteins. This research was shared by Nobel Prize in Chemistry With Thomas Steitz and Venkataraman Ramakrishnan.
For the Haydan website, Yonath's story is not just a Nobel Prize story. Over the years, I have covered her work many times, interviewed her on the eve of receiving the prize in Stockholm, and met her again at conferences where she continued to speak about one of the important practical implications of ribosome research: the fight against bacterial resistance toantibiotics.
"I didn't know there was a profession called scientist"
In an interview I conducted with Yonath at the Weizmann Institute in December 2009, days before the Nobel Prize ceremony, she described a life path that did not begin with a dream of becoming a researcher. "I didn't know there was a profession called a scientist," she said at the time.
She said that she studied chemistry at the Hebrew University because she loved both chemistry and physics, and later switched to biochemistry and biophysics. It was only when she arrived at the Weizmann Institute for doctoral studies and got to know people who were engaged in research out of curiosity that she realized that science could be a profession and a whole life.
Yonath was born in Jerusalem in 1939 to a poor family. Her father died when she was young, and she began working as a child to help support the family. She later studied chemistry and biochemistry at the Hebrew University, and received her doctorate inCrystallography She completed her degree in X-rays at the Weizmann Institute in 1968. After further training in the United States, she returned to the institute, and in 1970 she established the first laboratory in Israel for protein crystallography.
Research that others thought was impossible
In the late 70s, Yonat chose to tackle one of the most difficult problems in structural biology: determining the structure of the ribosome. To do this, it was necessary to create crystals of a huge, complex, and unstable biological complex—a task that many in the scientific community thought was impractical.
The Weizmann Institute notes that Yonat and her colleagues performed about 25,000 experiments before they succeeded in creating the first crystals of RibosomesEven then, the road to atomic-resolution decoding took about two more decades.
During her work, Yonat was a pioneer in cryobiocrystallography – the rapid freezing of biological crystals, which reduces the damage caused to them by strong X-ray radiation. Over the years, the method has become a widely accepted and important tool inStructural biology.
In 2000, groups led by her at the Weizmann Institute and a research unit of the Max Planck Society in Germany deciphered the complete 3D structures of the two subunits of a bacterial ribosome. A year later, Yonat and her colleagues were able to show at the structural level how various antibiotics bind to the ribosome and prevent bacteria from producing proteins.
For these studies, she won the Nobel Prize in Chemistry in 2009.
Almost moved to Rafael
One of the surprising stories that Yonat told me in an interview in 2009 took place many years earlier, at a time when her position at the Weizmann Institute was not yet guaranteed.
According to her, after the Yom Kippur War, while she was a young scientist, she helped Rafael people with software designed to improve the accuracy of missiles. At that time, she found out almost by chance that the institute was considering terminating her employment. But then a request came from Rafael asking to recruit her for a permanent position. Shortly thereafter, her appointment at the Weizmann Institute was extended.
In retrospect, this is an anecdote that illustrates the extent to which the scientific career that later became an international success story was not at all guaranteed in advance.
From the ribosome to antibiotics
Deciphering the structure of the ribosome was not just a basic science achievement. It gave researchers a way to understand how antibiotic drugs bind to bacterial ribosomes, how they disrupt protein production, and how changes in the ribosome can confer drug resistance to bacteria.
In 2012, I covered Yonath's keynote speech at the Life Sciences Baltics conference in Vilnius, where she warned against the lack of economic viability that pharmaceutical companies attribute to the development of new antibiotics, because unlike drugs for chronic diseases, antibiotics are usually taken for short periods of time.
"If companies don't think and act quickly, we will quickly return to the pre-antibiotic era within 20-30 years," she warned at the time.
Since then, bacterial resistance to antibiotics has become one of the main threats to public health worldwide – and the seminal work that Yonatan led continues to serve as a basis for understanding drug targets and designing new antibiotics.
Also the question of the origin of life
In recent years, Yonath's group has also continued to investigate an even more fundamental question: how the first systems that produced proteins arose at the beginning of life.
Yonath and her colleagues proposed that at the heart of the modern ribosome is a remnant of a much more ancient and simpler structure – a "protoribosome" – a kind of symmetrical RNA pocket that could have encouraged the formation of bonds between amino acids even before cells as we know them existed.
In 2022, the Weizmann Institute reported on experiments in which synthetic structures simulating that ancient pocket were built in the laboratory. The researchers showed that the structures were stable and suitable for forming bonds between amino acids, a finding that supported the idea that the modern ribosome carries at its heart a relic from the transition from pre-biological chemistry to life.
A scientist who insisted on big questions
Weizmann Institute President Prof. Alon Chen said upon the announcement of her death that Yonath did not hesitate to choose a path that others considered impossible and to persevere in it for decades. He said that her legacy is not limited to the breakthrough in the ribosome, but also to the example she set for generations of scientists.
Looking back, this is perhaps the thread connecting the various stations in her life: a girl from Jerusalem who didn't know there was a profession called scientist, a young researcher who almost lost her job, a scientist who insisted on a problem that was considered unsolvable, and a Nobel Prize winner who continued to work on ribosomes, antibiotics, and the origin of life even after winning.
Yonath herself did not like to turn the scientist into a celebrity. From the meetings and interviews with her, the impression that remained was that for her the prize was a result of the research – not a substitute for research. Even after she had won the highest global recognition, she continued to ask what else could be understood from the molecular machine to which she had dedicated her life.
Questions and Answers
What did Ada Yonath win the Nobel Prize for?
Ada Yonath won the 2009 Nobel Prize in Chemistry, together with Thomas Steitz and Venkataraman Ramakrishnan, for studies that revealed the structure and function of the ribosome at the atomic level.
What is a ribosome?
The ribosome is the molecular machine in the cell that translates the genetic information in messenger RNA into a chain of amino acids, which is then folded into a protein.
What is the connection between Yonat's work and antibiotics?
Structural studies of the ribosome have made it possible to see how antibiotics bind to bacterial ribosomes and interfere with protein production. This knowledge helps to understand drug resistance and design new antibiotics.
How long did Ada Yonat continue to engage in research?
According to the Weizmann Institute, Yonat continued to run an active laboratory, publish articles, and conduct scientific collaborations until her last days.
More on the subject on the science website
- "I didn't know there was such a profession as a scientist until I came to the Weizmann Institute to study for a doctorate and saw how they work here"
- Ada Yonat from the Weizmann Institute won the Nobel Prize in Chemistry
- The reluctance of pharmaceutical companies to develop new antibiotics for economic reasons could set us back decades when it comes to life expectancy
- Prof. Ada Yonat: It is possible that the missing link between pre-life and biological life has been discovered
- Prof. Ada Yonat's speech of thanks as part of the festive event on the evening of the awarding of the prize
Weizmann Institute announcement on the passing of Prof. Ada Yonath
