In an autobiography he wrote for the Royal Swedish Academy of Sciences in 2009, Thomas Steitz recalled learning about atomic orbitals in his introductory chemistry course at Lawrence College. He was struck by how details at the atomic level can inform us about chemicals’ overarching properties.

“It was a wonderful revelation to me about how the world around me could be understood,” he wrote.

Steitz, a Sterling Professor of molecular biophysics and biochemistry awarded with the 2009 Nobel Prize in Chemistry, died on Wednesday after a battle with pancreatic cancer. He was 78. He is survived by his wife, Sterling Professor of molecular biophysics and biochemistry Joan Steitz, his son Jon Steitz ’02 LAW ’07, daughter-in-law Katherine Van Loon Steitz SPH ’02 and two grandchildren.

“There are a lot of scientists who go through their careers and have one signature accomplishment, and in fact, most of us think that we’re very lucky to do that,” said chemistry professor Peter Moore ’61, a close collaborator and friend of Steitz’s. “There are probably half a dozen in Professor Steitz’s career. He was a truly exceptional scientist.”

Steitz was a biologist whose life’s work centered around determining the structures of the proteins essential for gene expression. He won the Nobel Prize for cracking the structure of the ribosome — the linchpin in the gene system.

Genes are expressed according to what is called the central dogma of molecular biology. DNA is transcribed into RNA, which is then translated into proteins. Ribosomes are the code-switchers in the process: They read RNA bases and translate that information into amino acids, the building blocks of proteins.

Steitz shed light on the translation process using a technique called X-ray crystallography. Proteins, like rock candy, can make crystals under the right conditions. Once crystallized, scientists can shoot X-rays through many copies of a protein and develop a composite structure of it.

Before joining Yale’s faculty in 1970, Steitz worked at the University of California, Berkeley for two months, resigning after the institution would not hire his wife. Joan Steitz told The New York Times that at the time, the chairman of biochemistry said to her, “All our wives like being research associates.”

“I think my dad was very much before his time in thinking that … women scientists should have every right to succeed,” Jon Steitz said.

Along with Moore and MB&B professor Donald Engelman GRD ’67, Steitz founded Yale’s first structural biology center in the mid-1970s. Grants from the National Institutes of Health and the Howard Hughes Medical Institute helped fund cutting-edge technology to put Yale’s center on the map.

“From the late ’80s to about 2000, we were arguably the dominant laboratory for structural biology in the United States, and Tom was leading the charge,” Moore said.

During that period, Steitz solved the structures of a number of proteins associated with the central dogma as well as one integral to how HIV infects its host. By 1995, his lab had provided insight into every step of the central dogma except the last one, involving the ribosome.

Moore attributed Steitz’s immense productivity throughout his career to his “intellectual courage.”

“Often you do something, make some progress and spend years cleaning up the campsite, dotting the i’s and crossing the t’s, and that was not [Steitz’s] style. His style was to move on,” Moore said.

The ribosome’s structure was the exception: Steitz and Moore spent five years working doggedly on it with three postdoctoral researchers — Poul Nissen, Nenad Ban and Jeff Hansen. Even then, the researchers could imagine the future impact of their discovery.

“We all knew that this was the ultimate project at the time,” said Nissen, now a professor of protein biochemistry at Aarhus University in Denmark. “It had this feeling that if we could do this, everything would be possible in the future.”

After Steitz was honored with the Nobel Prize for the discovery, colleagues said his behavior did not change at all; if anything, he became more dedicated to his research.

Ronald Breaker, a Sterling Professor of molecular, cellular and developmental biology, called Steitz “an incurable scientist.”

“I encountered him or his car in the Science Hill parking lot on enough weekends to make one think that he was working towards yet another Nobel Prize,” Breaker wrote in an email to the News.

The prize did, however, change the amount of attention and requests Steitz received from organizations around the world. Moore said Steitz’s personal schedule went “completely crazy” after 2009.

“I and my colleague Donald Engelman had lunch with him very regularly for 25 years, and we used to say to him, ‘Tom, just say no,’ and he never seemed to be able to do that very easily,” Moore said.

Jon Steitz said that even after receiving the cancer diagnosis, his father was reluctant to turn down meetings and speaking engagements planned for the fall. Thomas Steitz never wanted to be in the position of letting anyone down, his son added.

In Steitz’s autobiography for the Nobel committee, he emphasized the importance of teachers and advisers.

“Looking back over the development and progress of my career in science, I am reminded how vitally important good mentorship is in the early stages of one’s career development and constant face-to-face conversations, debate and discussions with colleagues at all stages of research. Outstanding discoveries, insights and developments do not happen in a vacuum,” he wrote.

Nissen and Karl Zahn, a current postdoctoral researcher in the Steitz Lab, commended Steitz for leading by example and offering constructive suggestions to them when they worked in his lab. Steitz genuinely cared about everyone in the lab and what they were working on, Zahn said.

Jon Steitz said his father’s willingness to learn from and support the people in his life helped make them successful. Jon, who pitched for the Milwaukee Brewers organization after being selected in the 2001 Major League draft, was passionate about baseball growing up, a pastime he said was completely foreign to his father. Nevertheless, Thomas Steitz did what he could to support his son.

“He went out and got all this catcher’s gear probably when I was about 10 or 11 to help me practice in the backyard,” Jon Steitz recalled. “He had no clue what he was doing, and even at the point where he ended up having some eye troubles and didn’t have much depth perception out of one side, he would still get out there with the catcher’s gear on and then stick his glove out and ask me to hit the glove.”

Thomas Steitz was also an avid gardener of roses. His hobby may have even made its way into his research: According to Zahn, a class of enzymes called DNA polymerases have a structure called a “thumb domain.” In Steitz’s lab, it was always colored green.

The Department of Molecular Biophysics and Biochemistry will hold a scientific symposium in Steitz’s honor on Jan. 18. Steitz’s family has also established an endowment for the Thomas Steitz Memorial Lecture Series in the Department of Molecular Biophysics and Biochemistry at Yale School of Medicine.

Madison Mahoney contributed reporting.

Maddie Bender | madeline.bender@yale.edu .