My watch list  

Low Charge and Reduced Mobility of Membrane Protein Complexes Has Implications for Calibration of Collision Cross Section Measurements

Ion mobility mass spectrometry of integral membrane proteins provides valuable insights into their architecture and stability. Here we show that, due to their lower charge, the average mobility of native-like membrane protein ions is approximately 30% lower than that of soluble proteins of similar mass. This has implications for drift time measurements, made on traveling wave ion mobility mass spectrometers, which have to be calibrated to extract collision cross sections (Ω). Common calibration strategies employ unfolded or native-like soluble protein standards with masses and mobilities comparable to the protein of interest. We compare Ω values for membrane proteins, derived from standard calibration protocols using soluble proteins, to values measured using an RF-confined drift tube. Our results demonstrate that, while common calibration methods underestimate Ω for native-like or unfolded membrane protein complexes, higher mass soluble calibration standards consistently yield more accurate Ω values. The...

Authors:   Timothy M. Allison; Michael Landreh; Justin L. P. Benesch; Carol V. Robinson
Journal:   Analytical Chemistry
Year:   2016
DOI:   10.1021/acs.analchem.6b00691
Publication date:   13-May-2016
Facts, background information, dossiers
More about American Chemical Society Publications
Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE