The Bush Lab is a research group in the Department of Chemistry and the Biological Physics, Structure & Design Program at the University of Washington. Our research focuses on the development and application of mass spectrometry and ion mobility spectrometry techniques to elucidate the structures and assembly of protein complexes and subcellular machines.

  • Interested in joining the Bush Lab? Click here.
  • Our weekly group meetings are held on Tuesdays at 5:15 PM in CHL 068B.

Recent Semiars

Prof. Bush recently presented the following seminars:

New Publication: Ion Mobility of Peptide Ions

Ion Mobility of Peptide Ions

One difficulty in using ion mobility (IM) mass spectrometry (MS) to improve the specificity of peptide ion assignments is that IM separations are performed using a range of pressures, gas compositions, temperatures, and modes of separation, which makes it challenging to rapidly extract accurate shape parameters. We report collision cross section values (Ω) in both He and N2 gases for 113 peptide ions determined directly from drift times measured in a low-pressure, ambient temperature drift cell with radio-frequency (rf) ion confinement. These peptide ions have masses ranging from 231 to 2969 Da, ΩHe of 89–616 Å2, and ΩN2 of 151–801 Å2; thus, they are ideal for calibrating results from proteomics experiments. These results were used to quantify the errors associated with traveling-wave Ω measurements of peptide ions and the errors concomitant with using drift times measured in N2 gas to estimate ΩHe. More broadly, these results enable the rapid and accurate determination of calibrated Ω for peptide ions, which could be used as an additional parameter to increase the specificity of assignments in proteomics experiments.

Ion Mobility Mass Spectrometry of Peptide Ions: Effects of Drift Gas and Calibration Strategies Matthew F. Bush, Iain D. G. Campuzano, Carol V. Robinson. Anal. Chem. 201284, 7124–7130.

Bush Lab at the Cascadia Proteomics Symposium

Cascadia Proteomics Symposium

The Bush Lab and collaborators are presenting the following talks at the Cascadia Proteomics Symposium, which takes place at the Institute for Systems Biology in Seattle from July 19-21.

  • Samuel T. Marionni; Weiman Xing; Ning Zheng; Matthew F. Bush. Ion Mobility Mass Spectrometry of a Circadian Clock Protein Complex Reveals a Ligand-Dependent Conformational Switch (Thursday @ 4:40 pm)
  • Samuel J. Allen; Samuel T. Marionni; Kevin Giles; Tony Gilbert; Matthew F. Bush. Design and Characterization of a New Ion Mobility Cell (Saturday @ 9:50 am)

New Publication: Dissecting Heterogeneous Molecular Chaperone Complexes

Small heat-shock proteins (sHSPs) are molecular chaperones that prevent irreversible aggregation through binding nonnative target proteins. Due to their heterogeneity, the resulting sHSP:target complexes remain poorly understood. We developed a general and automated approach for estimating the distribution of stoichiometries for heterogeneous ensembles of protein complexes. Using this approach, we find that the stoichiometries of sHSP:target complexes depend on both the mass and quaternary architecture of the target, indicating that protection occurs early during denaturation. This investigation therefore explains the apparent paradox of how variable, complex morphologies result from the generic sHSP protection mechanism.

For a perspective on this work, please see Breaking Down Order to Keep Cells Tidy, a preview written by Christine Slingsby and Alice Clark (Birkbeck College).

Dissecting Heterogeneous Molecular Chaperone Complexes Using a Mass Spectrum Deconvolution Approach Florian Stengel, Andrew J. Baldwin, Matthew F. Bush, Gillian R. Hilton, Hadi Lioe, Eman Basha, Nomalie Jaya, Elizabeth Vierling, Justin L.P. Benesch. Chem. Biol. 201219, 599–607.