Article abstract
Nature Methods 6, 817 - 823 (2009)
Published online: 18 October 2009 | doi:10.1038/nmeth.1390
Visual proteomics of the human pathogen Leptospira interrogans
Martin Beck1,5, Johan A Malmström1,5, Vinzenz Lange1, Alexander Schmidt1, Eric W Deutsch2 & Ruedi Aebersold1,2,3,4
Abstract
Systems biology conceptualizes biological systems as dynamic networks of interacting elements, whereby functionally important properties are thought to emerge from the structure of such networks. Owing to the ubiquitous role of complexes of interacting proteins in biological systems, their subunit composition and temporal and spatial arrangement within the cell are of particular interest. 'Visual proteomics' attempts to localize individual macromolecular complexes inside of intact cells by template matching reference structures into cryo-electron tomograms. Here we combined quantitative mass spectrometry and cryo-electron tomography to detect, count and localize specific protein complexes in the cytoplasm of the human pathogen Leptospira interrogans. We describe a scoring function for visual proteomics and assess its performance and accuracy under realistic conditions. We discuss current and general limitations of the approach, as well as expected improvements in the future.
- Institute of Molecular Systems Biology, The Swiss Federal Institute of Technology (ETH Zurich), Zurich, Switzerland.
- Institute for Systems Biology, Seattle, Washington, USA.
- Faculty of Science, University of Zurich, Zurich, Switzerland.
- Center for Systems Physiology and Metabolic Diseases, Zurich, Switzerland.
- These authors contributed equally to this work.
Correspondence to: Ruedi Aebersold1,2,3,4 e-mail: aebersold@imsb.biol.ethz.ch
