Metals in Biochemistry

The symposium in honor of Elizabeth Theil, 2008 Garvan-Olin Medalist, was sponsored by the American Chemical Society Division of Inorganic Chemistry (INOR) and cosponsored by the Women Chemists Committee.  This full-day symposium was organized and presided over by John Magyar, Barnard College, and Harry B. Gray, Beckman Institute at the California Institute of Technology. Elizabeth's research at Children’s Hospital Oakland Research Institute focuses on ferritin, the iron protein complex that manages iron and oxygen levels in vivo.  Elizabeth's impact as a mentor for scientists researching the interface between biology and chemistry was obvious from the memories of science, history, and personal interactions shared by the other speakers.  Such memories included the story of the largest ferritin molecule, an architectural model at the Beckman Institute. 

JoAnne Stubbe, Massachusetts Institute of Technology, led off the morning session with a report on the assembly and maintenance pathways of the diferric-tyrosyl cofactors in ribonucleotide reductase, speaking of the rolls of biological redundancy and differences between in vitro and in vivo mechanisms.  Joan Valentine, University of California at Los Angeles, spoke of the roles of manganese salts in antioxidant protection of aerobic cells that lack superoxide dismutase.  John Magyar, Barnard College, directs the research of undergraduate students, who gather materials from sites as far apart as Antarctica and the La Brea Tar Pits to study the role of transition metal ions as trace nutrients in the major metabolic cycles.  Stephen Lippard, Massachusetts Institute of Technology, working in the new area of metalloneuro-chemistry, appends zinc to fluorescently labeled metal-chelating units.  With sensors programmed to visualize zinc in damaged neuronal cells, his research may potentially gain insight into mechanisms of neurological diseases such as Alzheimer's, where a lack of zinc is a notable characteristic. The morning session concluded with a talk by Harry Gray, Beckman Institute at Caltech, on electron flow through metalloproteins.  His group has recently found that 20-angstrom pore hopping through intervening tryptophan residues is more efficient than single step electron tunneling.

Ivano Bertini, Magnetic Resonance Center at the University of Florence, Italy, opened the afternoon session with a talk on the value of heteronuclear detection methods for the study of metalloproteins.  Akif Tezcan, University of California at San Diego, spoke of the use of non-natural ligands to control protein-protein or metal-protein interactions responsible for metalloprotein self assembly.  In a similar vein, Carol Fierke, University of Michigan, spoke of metal switching as a potential mechanism for regulation of metalloenzyme reactions.  Ivan Dmochowski, University of Pennsylvania, moderator for the afternoon session, called ferritin a well-rounded protein with roles in nanomaterials, bioinorganic, and medicinal chemistry.  To conclude the symposium, Elizabeth gave a tour of the ferritin molecule from start to finish, with questions yet to be addressed.

-Ellie Brown