2009 3M/Ronald A. Mitsch Lecture in Chemistry “The Aging Brain and What We are Trying To Do About It.” Dr. Gregory PetskoProfessor of biochemistry and molecular pharmacodynamics and chair of the Department of Biochemistry at Brandeis University. Through the study of the three-dimensional structures and biochemical functions of proteins, he will bring a chemical perspective to bear on problems in biochemistry, structural biology, cell biology, and human health. In 1990, he was appointed the Lucille P. Markey Professor in Biochemistry and Chemistry at Brandeis University. He has served as director of the Rosenstiel Basic Medical Sciences Research Center at Brandeis University, and, since 1996, he has held the title of Gyula and Katica Tauber Professor of Biochemistry and Molecular Pharmacodynamics there. Petsko has received numerous awards, including the Sidhu Award of the American Crystallographic Association for outstanding contributions to X-ray diffraction, the Pfizer Award in Enzyme Chemistry of the American Chemical Society, and an Alexander von Humboldt Senior Scientist Award. He was also awarded the Max Planck Prize for work on the origins of some human cancers and has received a Guggenheim Fellowship. In addition to his role at Brandeis, Petsko is also an adjunct professor for the Department of Neurology at Harvard Medical School and is president of the American Society for Biochemistry and Molecular Biology. He graduated summa cum laude from Princeton University and received a Rhodes Scholarship to Oxford University, where he completed his doctoral research. He was an assistant professor of biochemistry at Wayne State University School of Medicine and later served as an associate professor of chemistry and then as professor of chemistry at the Massachusetts Institute of Technology.