02/10/20 - 4:00 PM to 5:00 PM
Kolthoff Lectureship #1: Professor Catherine L. Drennan
Izaak M. Kolthoff Lectureship in Chemistry
The Great (and Less Great) Metallocofactors of Biology
How do microbes live on the pollutant carbon monoxide? How do microbes split the triple bond of nitrogen gas? When it comes to performing difficult chemistry, microbes often combine a protein scaffold with a highly reactive metallocofactor, employing a hired gun, if you will. Some of these metallocofactors are relatively simple – a single iron atom bound to an enzyme, whereas others are complex, and are best described as multi-metal assemblies or as “great metallocofactors.” In this presentation, audience members will hear about one “great” cluster: the nickel-iron-sulfur cluster of the enzyme carbon monoxide dehydrogenase (CODH), and one “less great” cluster: a mononuclear iron atom coordinated by the enzyme methylphosphonate synthase (MPnS). Whereas the “great” metallocofactor of CODH (aka the C-cluster) enables microbes to live on carbon monoxide, the “less great” mononuclear iron cofactor should not be undersold. Iron-dependent MPnS biosynthesizes methylphosphonate, the compound that is thought to be the source of methane from the upper aerobic ocean. We will consider how “great metallocofactors” are made and how they work. We will also consider how enzymes tune the reactivity of a single iron ion to afford novel reactivity.
Catherine Drennan is a professor of chemistry and biology at the Massachusetts Institute of Technology, and a professor and investigator with the Howard Hughes Medical Institute.
Professor Drennan’s primary research interest is the use of X–ray crystallography to study the structure and mechanism of metalloproteins. The primary targets of research in the Drennan lab are enzymes that contain metals or metallocofactors. These metalloenzymes use the enhanced reactivity of transition metals to catalyze challenging chemical reactions including radical-based chemistry and manipulation of organometallic bonds. The lab is also interested in metalloproteins that sense changes in the cellular environment and act as gene regulators. The Drennan lab also combines X-ray crystallography and electron microscopy with other techniques from biochemistry and biophysics to understand enzyme mechanisms—an approach called “structural metalloenzymology.”
Professor Drennen's educational initiatives include creating free resources for educators that help students recognize the underlying chemical principles in biology and medicine, and that train graduate student teaching assistants and mentors to be effective teacher–scholars.
Her awards include the Howard Hughes Medical Institute Investigator, Howard Hughes Medical Institute Professor, Everett Moore Baker Memorial Award for Excellence in Undergraduate Teaching, Harold E. Edgerton Faculty Achievement Award, Dean’s Educational and Student Advising Award, Alfred P Sloan Fellow, American Society of Biochemistry and Molecular Biology (ASBMB)–Schering–Plough Research Institute Scientific Achievement Award, Presidential Early Career Award for Scientists and Engineers, Searle Scholar, Cecil and Ida Green Career Development Chair, and Surdna Foundation Research Award.
Professor Drennan received an AB (artium baccalaureus) in chemistry from Vassar College, and a doctorate in biological chemistry from the University of Michigan. She was also a post-doctoral fellow at the California Institute of Technology before joining the faculty at the Massachusetts Institute of Technology.
Kolthoff Lectureship in Chemistry
Izaak Maurits Kolthoff was born on February 11, 1894, in Almelo, Holland. He died on March 4, 1993, in St. Paul, Minnesota. In 1911, he entered the University of Utrecht, Holland. He published his first paper on acid titrations in 1915. On the basis of his world-renowned reputation, he was invited to join the faculty of the University of Minnesota’s Department of Chemistry in 1927. By the time of his retirement from the University in 1962, he had published approximately 800 papers. He continued to publish approximately 150 more papers until his health failed. His research, covering approximately a dozen areas of chemistry, was recognized by many medals and memberships in learned societies throughout the world, including the National Academy of Sciences and the Nichols Medal of the American Chemical Society. Best known to the general public is his work on synthetic rubber. During World War II, the government established a comprehensive research program at major industrial companies and several universities, including Minnesota. Kolthoff quickly assembled a large research group and made major contributions to the program. Many of Kolthoff’s graduate students went on to successful careers in industry and academic life and, in turn, trained many more. In 1982, it was estimated that approximately 1,100 Ph.D. holders could trace their scientific roots to Kolthoff. When the American Chemical Society inaugurated an award for excellence in 1983, he was the first recipient.
Event DetailsLocation: 331 Smith HallHost: Professor Ambika Bhagi-Damodaran