Dr. John Rubinstein
Molecular Structure and Function Program
The Hospital for Sick Children
Toronto, Ontario Canada

Monday, April 7, 2008
3:00 pm (CT)
3269 Beckman Institute

Abstract

Adenosine triphosphate (ATP) is the nearly universal energy currency used in biology. The multiprotein enzyme ATP synthase, found in the inner membrane of mitochondria and chloroplasts of eukaryotes and the cytoplasmic membrane of eubacteria, is responsible for the synthesis of ATP by a remarkable rotary catalytic mechanism. We have employed electron cryo-microscopy of single particles (cryo-EM) to determine the structure of bovine and yeast ATP synthase. Calculating the 3-D structure of ATP synthase from cryo-EM images has required significant methodological innovation, such as the creation of the “rotational analysis” method and continued efforts to improve computation in order to push our models to higher resolution. Molecular genetic tools have allowed us to implement tagging strategies to localize individual subunits within the low-resolution EM maps. Combination of our maps with atomic models from X-ray crystallography and NMR spectroscopy has lead to an atomic interpretation of some portions of the complex.