Chapter 11. Mass Spectrometry of Membrane Transport Proteins

  1. Michael W. Quick Ph.D.
  1. Julian P. Whitelegge1,
  2. H. Ronald Kaback2 and
  3. Johannes le Coutre3

Published Online: 19 MAR 2003

DOI: 10.1002/0471434043.ch11

Transmembrane Transporters

Transmembrane Transporters

How to Cite

Whitelegge, J. P., Kaback, H. R. and le Coutre, J. (2002) Mass Spectrometry of Membrane Transport Proteins, in Transmembrane Transporters (ed M. W. Quick), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/0471434043.ch11

Editor Information

  1. Department of Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA

Author Information

  1. 1

    The Pasarow Mass Spectrometry Laboratory, Departments of Psychiatry and Biobehavioral Sciences, Chemistry and Biochemistry and The Neuropsychiatric Institute, University of California, Los Angeles, CA, USA

  2. 2

    Howard Hughes Medical Institute, Departments of Physiology and Microbiology, Immunology and Molecular Genetics, and the Molecular Biology Institute, University of California at Los Angeles, Los Angeles, CA, USA

  3. 3

    Nestlé Research Center, Bioscience Department, Lausanne, Switzerland

Publication History

  1. Published Online: 19 MAR 2003
  2. Published Print: 23 AUG 2002

Book Series:

  1. Receptor Biochemistry and Methodology

Book Series Editors:

  1. David R. Sibley

Series Editor Information

  1. Molecular Neuropharmacology Section, Experimental Therapeutics Branch, NINDS, National Institutes of Health, Bethesda, Maryland, USA

ISBN Information

Print ISBN: 9780471065135

Online ISBN: 9780471434047

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Keywords:

  • proteomics;
  • membrane protein;
  • symport;
  • post-translational modification;
  • protein oxidation;
  • transport mechanism;
  • membrane protein structure

Summary

The lactose permease from Escherichia coli is a paradigm for an integral membrane transport protein. Based on liquid-chromatography electrospray ionization mass-spectrometry (LC-ESI-MS) a technology has been developed to characterize the covalent structure of this class of membrane proteins. Accuracy and resolution of the technique permit detection of subtle covalent modifications such as oxidation or alkylation of the protein. Monitoring changes of the molecular weight under defined and specific conditions in combination with site directed mutagenesis is a powerful tool to develop a detailed picture of the transport mechanism on the atomic level. Using inactive single-Cys D240C permease it is demonstrated that the thiol group of C240 can be oxidized via sulfenic and sulfinic acid to a sulfonic acid. Moreover, correlating the time course of oxidation with activity measurements demonstrates that only the sulfinic acid at position 240 is able to mimic the native aspartate with respect to recovery of activity.