Stephen J. Lippard

Image
Franklin Institute 2015 laureate Stephen J. Lippard.
Stephen J.
Lippard
Year
2015
Subject
Chemistry
Award
Benjamin Franklin Medal
Affiliation
Massachusetts Institute of Technology │ Cambridge, Massachusetts
Citation
For his pioneering research on the role of metal atoms in biology and medicine, including the study of platinum anticancer drugs and of the structure and function of an enzyme that allows microbes to live on natural gas.

To the layperson, chemistry is divided into two separate realms: organic, which studies the dizzyingly complex ways of carbon atoms, and inorganic, which basically studies everything else. But in truth, the two areas are hardly separate and distinct, and chemists often cross that rather artificial divide in their professional work. One prominent example is the field of bioinorganic chemistry. As a pioneer of the field, Stephen Lippard has made major contributions in the study and development of anticancer drugs, enzymatic function, and protein characterization and synthesis.

While the term may seem oxymoronic at first, bioinorganic chemistry is the study of how nonliving substances, specifically metals, affect and interact with biological organisms and systems. Lippard first encountered the subject while an undergraduate at Haverford College. He abandoned his original plans to go on to medical school when the Australian inorganic chemist Francis P.J. Dwyer visited the college. Fascinated by Dwyer's work on medicinal chemistry, Lippard switched his focus to inorganic chemistry as he entered graduate school at MIT.

His interests in medical biology never wavered, however, and after earning his doctorate from MIT in 1965 and joining the faculty of Columbia University, Lippard began to integrate that interest into his professional specialty of inorganic chemistry. He studied the platinum-based family of anticancer drugs, chiefly cisplatin. Though its anticancer properties had been known for some time, with platinum drugs now used to treat about half of all patients with solid tumors, the drug's precise workings remained a mystery. Through X-ray crystallographic studies of cisplatin bound to DNA fragments, Lippard elucidated the mechanisms by which cisplatin invades malignant cells to disrupt their DNA functions and destroy cancer. This trailblazing work has the potential to benefit innumerable cancer patients by providing doctors with a better understanding of this major chemotherapy drug and allowing the formulation of more effective drug candidates that will soon enter the clinic.

Another major research area in which Lippard has bridged the gap between the organic and the inorganic concerns the binuclear enzyme methane monooxygenase (MMO). Making it possible for bacteria to oxygenate methane and produce methanol, MMO is not only a vital element of the Earth's life-sustaining carbon cycle, but also provides clues toward the creation of synthetic methanol-based fuels. Lippard elucidated the structures of MMO's component proteins through a variety of methods, including X-ray diffraction, and developed the synthesis and structural characterization of model compounds. His detailed descriptions of the structure and mechanisms of MMO have vastly increased our knowledge of this important interface between the living and nonliving, enhancing its potential for developing clean fuel technologies.

Most recently, Lippard has expanded his research palette to encompass a new discipline called metalloneurochemistry. This field studies the role that metals play in the functions and maladies of the brain and nervous system. He has developed techniques using fluorescence and MRI for sensing the presence and distribution of zinc and other metallic ions in the human brain, providing new insights into how these elements contribute to signaling activity. 

Stephen Lippard's seminal scientific work has been widely recognized by many prestigious honors, including the National Medal of Science, the Linus Pauling Medal, the Joseph Priestley Medal of the American Chemical Society, and election to the National Academy of Sciences.

But his gifts as an educator to hundreds of graduate and postdoctorate students as well as countless undergraduates are as famous as his scientific work. He returned to MIT in 1983 and has been there ever since, serving as head of the chemistry department from 1995 to 2005. Aside from co-authoring a major textbook in his field, Principles of Bioinorganic Chemistry, he has worked as associate editor of the Journal of the American Chemical Society for more than 30 years and served on numerous other editorial boards, while publishing more than 800 papers.

One of Lippard's most important roles throughout his entire career has been as a champion for women in science. In his field of chemistry, where women are still relatively rare, Lippard has tirelessly worked to encourage and support his female students. About 40 % of the graduate students Lippard has mentored over the course of his teaching career have been women, many of whom have gone on to brilliant scientific careers of their own.

An accomplished harpsichordist in his spare time, Lippard likes to compare chemistry to music, noting that a chemist needs to have both an artistic side and a more analytical bent, much like a musician or a conductor putting together melodies and orchestrating different instruments. Stephen Lippard's career both as a scientist and as an educator stands as an exemplar of that philosophy, bringing together seemingly unrelated and separate strands of knowledge into a harmony of new understanding.

Information as of April 2015