91ÑÇÉ«´«Ã½

Growing up in Beaumont, Texas, with an uncle who worked at NASA, ’s first childhood scientific love was astronomy. Another uncle was a math professor at a local university, and between the two, Booker’s lifelong interest in science was sparked.

After studying chemistry at Austin College, Booker earned his Ph.D. from the Massachusetts Institute of Technology. He researched an enzyme involved in DNA synthesis called ribonucleotide reductase that uses free electrons, called radicals, to facilitate a chemical reaction — this was his introduction into the world of radical chemistry.

Squire Booker

After graduate school, Booker went to Paris on a National Science Foundation–NATO fellowship to do research at the Université René Descartes and then took a second postdoc at the University of Wisconsin in the Institute for Enzyme Research. There, he continued to study how enzymes use radicals to catalyze reactions.

“During my second postdoc, doing enzyme research, was when I started getting interested in iron–sulfur clusters and how they were involved in radical chemistry,” Booker said.

Enzymes that rely on radicals can generate and use the radicals in many different ways, some depending on associated groups called co-factors. Around the time Booker was starting his second postdoc, a researcher at Wisconsin described a new mechanism that enzymes use to make radicals that involves iron–sulfur clusters, a widespread and ancient metal co-factor, and a molecule called S-adenosylmethionine, abbreviated SAM. The radical SAM superfamily was named after this discovery.

“The radical SAM superfamily of enzymes just blossomed into this incredibly large group of enzymes that catalyze an amazing array of different types of reactions,” Booker said. “And they all need to have iron–sulfur clusters to generate the radicals.”

Booker, now a professor at the Pennsylvania State University and a Howard Hughes Medical Institute investigator, has dedicated much of his research to understanding the structure and function of enzymes with iron–sulfur clusters, with particular focus on radical SAM enzymes. In recognition of his work, Booker has won the 91ÑÇÉ«´«Ã½’s 2023 91ÑÇÉ«´«Ã½–Merck Award, which honors outstanding research in biochemistry and molecular biology.

In his letter of nomination for the award, Penn State colleague J. Martin Bollinger credited Booker’s deep curiosity, technical acumen, creativity and courage with allowing “him to lead and even transcend the field” of enzymology research. Vahe Bandarian, a professor at the University of Utah, added that “Squire has the gift of being able to collaboratively solve complex problems.”

Of his research career, Booker said he has enjoyed the freedom to study what he’s most interested in.

“Other than scientific freedom, the other enjoyable aspect (of research) is working with and training young people and students,” he said, “and seeing them blossom into incredible scientists themselves and do incredible things on their own.”

Throughout his career, Booker has been committed to supporting young scientists, particularly those from historically underrepresented backgrounds. He helped establish and currently serves as principal investigator for the 91ÑÇÉ«´«Ã½ Interactive Mentoring Activities for Grantsmanship Enhancement, or IMAGE, workshop program, which is designed to teach early-career scientists and postdoctoral fellows how to write effective grant proposals.

Booker also serves on the advisory board and as a mentor for the 91ÑÇÉ«´«Ã½’s Maximizing Opportunities for Scientific and Academic Independent Careers, or MOSAIC, program, a National Institutes of Health–funded effort to enhance diversity within the academic biochemical research community.

In recognition of his work related to advocacy and outreach, Booker is also the recipient of the 91ÑÇÉ«´«Ã½’s 2023 Ruth Kirschstein Diversity in Science Award. This is the first time a single person has received two 91ÑÇÉ«´«Ã½ awards in the same year — a testament to Booker’s character and consistent efforts to advance science and expand the research community.

In her nomination letter for the Kirschstein award, Ruma Banerjee, a professor at the University of Michigan, described Booker as an “inspiring role model” and praised his “tireless and outstanding contributions to advancing STEM diversity.”

Booker said he was happy when he found out about both awards.

“I’m always excited to be recognized for my science, so I was thrilled about the Merck award,” he said. “I think my award and the Avanti Award in Lipids given to Russell Debose–Boyd is the first time an underrepresented minority (or at least an African American) has gotten a science award from 91ÑÇÉ«´«Ã½.”

Booker was on the 91ÑÇÉ«´«Ã½ team that helped conceptualize and implement the Kirschstein award, which he said was intended originally to help underrepresented minorities gain recognition and have a chance to give award talks at the society’s annual meeting. The 2023 award recognizes his long-standing efforts to make the sciences a more diverse and equitable place.

“I’m happy to get this particular award as well,” Booker said. “I’m happy that (the awards committee) recognized that I do the best I can to contribute to outreach to scientists.”