Nobel Laureate Signature Award for Graduate Education in Chemistry

Sponsored by Mallinckrodt Baker

Raquel L. Lieberman adored math as a child and thought she would be a chemical engineer. But she found a home in research that bridged chemistry and biology.

Lieberman's Ph.D. thesis focused on determining the structure of particulate monooxygenase (pMMO), an integral membrane metalloenzyme that catalyzes the oxidation of methane to methanol in methanotrophic bacteria. pMMO interests scientists involved in bioremediation and those trying to render methane as a realistic energy source.

"A third of all sequenced genomes encode membrane proteins," Lieberman says, "and for many of those, we have no idea what they do, let alone what they look like." Of the 25,000 crystal structures in the Protein Data Bank, fewer than 100 are membrane proteins because of difficulties in isolating and crystallizing them.

Her preceptor and Ph.D. adviser at Northwestern University, Amy C. Rosenzweig, says these issues made the project particularly challenging and made obtaining funding for it difficult. "What started out as one ambitious student toiling away at a risky project is now a full enterprise in my laboratory," she adds.

Lieberman characterized the elusive membrane protein and its metal centers with various biophysical methods while trying to obtain well-diffracting crystals of pMMO. She then spent huge amounts of time collecting X-ray data at synchrotron sources around the country and solved the crystal structure of the whole pMMO enzyme. Now, three graduate students and a postdoc carry on the project, propelled by funding from the National Institutes of Health.

Rosenzweig is excited about this award because other "awards just recognize faculty, but here's an award that actually recognizes the student."

Lieberman credits Rosenzweig as "a fantastic mentor" and says, "I really feel I could not have done this in a different lab."

"To have single-handedly accomplished all of these goals is an off-scale achievement," says Jonathan Widom, past-chair of the biochemistry, molecular biology, and cell biology department at Northwestern. "Altogether, Lieberman is on track to becoming a real star."

Lieberman, 29, grew up "in New York City surround sound" with two professional, classically trained musicians as parents. Lieberman attended Bronx High School of Science and worked after school in a biophysics lab at Mount Sinai School of Medicine. As a chemistry major at Massachusetts Institute of Technology, she minored in music and worked in Stephen J. Lippard's lab. In 1998, she was looking for a graduate adviser at Northwestern. "Based on the fact that she had worked in the same lab where I got my Ph.D., I was pretty interested in recruiting her into my group," Rosenzweig recalls. Lieberman liked the project and defended her dissertation in January 2005.

Now as a joint postdoctoral fellow between Harvard Medical School and Brandeis University, Lieberman is studying proteins implicated in Alzheimer's disease. She would like to run her own academic research group.

She also continues to discuss science with as many people as possible. "It is very important to me to try and bridge the gap between what scientists do on a daily basis and what the public perceives as what scientists do," Lieberman says. As a graduate student, among her activities, she judged the Chicago Citywide Science Fair, worked as a writing mentor for underrepresented undergraduate minorities doing summer research at Northwestern, and collaborated on articles that address work-life balance issues. In Boston, she plans to work with middle school students.

Rosenzweig, 39, received a B.A. in chemistry from Amherst College in Amherst, Mass., in 1988. In 1994, she earned her Ph.D. in inorganic chemistry from MIT and started a postdoctoral fellowship at Harvard University and the Dana Farber Cancer Institute in Boston, which was sponsored by NIH. Rosenzweig joined the departments of biochemistry, molecular biology, and cell biology and chemistry at Northwestern University as an assistant professor in 1997 and was promoted to associate professor in 2002 and to full professor in 2005.

She received the Camille Dreyfus Teacher-Scholar Award in 2001. Rosenzweig was named a MacArthur Fellow in 2003. In 2004, she became the Irving M. Klotz Research Professor at Northwestern.

The award address will be presented before the Division of Inorganic Chemistry.—Rachel Petkewich