Ada Yonath, Nobel laureate and crystallographer, dies at 87

Ada Yonath, a structural biologist and Nobel laureate who pioneered the technique of cryo bio-crystallography, died Aug. 31, at the age of 87, according to a release from the Weizmann Institute of Science.

Yonath was a corecipient of the 2009 Nobel Prize in Chemistry for her contributions to determining the structure of the ribosome. It was the first time a woman had won the chemistry prize in 45 years.

“She was very bold,” says Venkatraman Ramakrishnan of the Medical Research Council Laboratory of Molecular Biology, who shared the 2009 Nobel with Yonath and Yale chemist Thomas Steitz. “By showing that you could get 3D crystals of the large subunit, and then eventually showing that you could get crystals that diffracted to high resolution, she broke a very important psychological barrier to solving what seemed like an impossible problem,” he says.

Miri Krupkin, a postdoctoral researcher at Stanford University, did her PhD work with Yonath and calls her “the most brilliant but also the most humble scientist I know.” Krupkin adds that even as a young trainee she had felt “from the first moment that she respected me as a full-grown scientist.”

Yonath was born in 1939 in Jerusalem, in what was then the British-administered Mandatory Palestine, now Israel. She was the daughter of Polish immigrants and lived in poverty for much of her early life. Her father died when she was 11, and though she was burdened with additional responsibility to take care of her family as a child, her mother supported her pursuit of higher education.

But before she went to college, Yonath spent 2 years in the Israeli Medical Corps as part of her compulsory Army services. There she learned about clinical and medical issues that would inspire her to pursue studies in biochemistry at the Hebrew University of Jerusalem.

In her doctoral studies, Yonath was attracted to questions of structural biology and the technique of X-ray crystallography, which is used to map the position of atoms in a molecular structure. She earned her PhD from the Weizmann Institute in 1968 for research in which she used the technique to study the structure of collagen. Yonath then moved to the US for 2 years and completed two postdocs, one under Nobel laureate William Lipscomb.

When she returned to Israel, and the Weizmann, Yonath established and ran what was then the only crystallography lab in the country. She turned her attention to determining the structure of the ribosome—despite ridicule from other scientists who said the task was impossible.

Protein crystals, which are repeating lattice structures containing millions of proteins, are notoriously difficult to produce. But crystallizing the ribosome was considered impossible because the protein-RNA complexes are large, asymmetrical, and flexible—all characteristics that lead to poorly constructed crystal lattices.

Undeterred, Yonath took a fellowship at the Max Planck Institute for Molecular Genetics, working with one of the pioneers of ribosome research, Heinz-Günter Wittmann. She began trying to crystalize ribosomes isolated from a variety of species, and in 1980 she had success. Using ribosomes extracted from Bacillus stearothermophilus provided by Volker Erdmann, Yonath and Wittmann became the first people to obtain 3D crystals of the 50S large ribosomal subunit.

Then in the late 1980s, Yonath was visited at the Weizmann Institute by Håkon Hope, who was there to collaborate with Joel Sussman on a revived technique for supercooling crystals to maintain their stability during X-ray diffraction. The technique was first developed by David Haas and Michael Rossmann at the Weizmann Institute in the late 1960s, while Yonath was finishing her PhD. Together, Sussmann, Hope, and Yonath were able to apply the technique to ribosomes. Yonath would evangelize the technique, helping to popularize the new field of cryo bio-crystallography.

In 1991, after years of improvement making ribosome crystals using the cryo technique, Yonath would report that her lab had managed to make 50S ribosomal subunit crystals that diffracted to a 3 Å resolution (J. Mol. Biol., DOI: 10.1016/0022-2836(91)90730-t). The mid-1990s saw a race brewing to fully map out the ribosome, with many rivals participating. Ultimately, Yonath, Ramakrishnan, and Steitz were the three who shared the Nobel Prize.

Yonath continued with her crystallography work after the ribosome was mapped out and used the structure to better understand antibiotics, many of which attack bacterial ribosomes.

Krupkin says Yonath was “a fierce advocate for science and for science education” and recalls that she would often spend 24 h shifts helping her students when they managed to get beam time reserved at a synchrotron. She also supported young scientists by traveling to give talks and was very involved in the Lindau Nobel Laureate Meetings, which she attended again this summer.

Yonath also didn’t shy away from political activism. In 2009, shortly after learning about her Nobel, she spoke out on the Gilad Shalit hostage situation, saying that “holding Palestinians captive encourages and perpetuates their motivation to harm Israel and its citizens. . . . Once we don’t have any prisoners to release they will have no reason to kidnap soldiers.” More recently, she criticized the 2023 Israeli judicial reform as a peril to democracy and the Israeli scientific enterprise. She was also a signatory on petitions calling for aid to Israeli captives in Palestine and opposing the death penalty for Palestinian captives in Israel.

In addition to the Nobel Prize, Yonath received many awards in her lifetime, including the Wolf Prize in Chemistry, and was elected as a foreign member of the UK’s Royal Society, among other achievements. “She had many, many prizes in her office, hanging on the wall,” Krupkin says. “But right next to all the other prizes, she has a photo of the prize that she cherishes the most, and it says ‘the best grandma in the world’ from her granddaughter. That prize she says is the hardest because she has to renew it every year.”

Max Barnhart is an assistant editor and life sciences reporter at C&EN.