Issue 20, 2015

Ion mobility-mass spectrometry of charge-reduced protein complexes reveals general trends in the collisional ejection of compact subunits

Abstract

Multiprotein complexes have been shown to play critical roles across a wide range of cellular functions, but most probes of protein quaternary structure are limited in their ability to analyze complex mixtures and polydisperse structures using small amounts of total protein. Ion mobility-mass spectrometry offers a solution to many of these challenges, but relies upon gas-phase measurements of intact multiprotein complexes, subcomplexes, and subunits that correlate well with solution structures. The greatest bottleneck in such workflows is the generation of representative subcomplexes and subunits. Collisional activation of complexes can act to produce product ions reflective of protein complex composition, but such product ions are typically challenging to interpret in terms of their relationship to solution structure due to their typically string-like conformations following activation and subsequent dissociation. Here, we used ion–ion chemistry to perform a broad survey of the gas-phase dissociation of charge-reduced protein complex ions, revealing general trends associated with the collisional ejection of compact, rather than unfolded, protein subunits. Furthermore, we also discover peptide and co-factor dissociation channels that dominate the product ion populations generated for such charge reduced complexes. We assess both sets of observations and discuss general principles that can be extended to the analysis of protein complex ions having unknown structures.

Graphical abstract: Ion mobility-mass spectrometry of charge-reduced protein complexes reveals general trends in the collisional ejection of compact subunits

Supplementary files

Article information

Article type
Paper
Submitted
05 رمضان 1436
Accepted
07 ذو القعدة 1436
First published
09 ذو القعدة 1436

Analyst, 2015,140, 7020-7029

Author version available

Ion mobility-mass spectrometry of charge-reduced protein complexes reveals general trends in the collisional ejection of compact subunits

R. E. Bornschein and B. T. Ruotolo, Analyst, 2015, 140, 7020 DOI: 10.1039/C5AN01242B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements