Surface-Induced Dissociation of Anionic vs Cationic Native-like Protein Complexes
2021
Characterizing protein-protein
interactions, stoichiometries, and subunit connectivity is key to understanding
how subunits assemble in biologically relevant multi-subunit protein complexes.
Native mass spectrometry (nMS) has emerged as a powerful tool to study protein complexes
due to its low sample requirements and tolerance for heterogeneity. For such
nMS studies, positive mode ionization is routinely used and charge reduction,
through the addition of solution additives, is often used, as the resulting
lower charge states are often more compact and considered more native like.
When studied with surface-induced dissociation, charge reduced complexes often
give increased structural information over their “normal-charged” counter
parts. A disadvantage of charge-reduction is that increased adduction, and
hence peak broadening, is often observed when charge-reducing solution
additives are present. Recent studies have shown that protein complexes ionized
using negative mode generally form in lower charge states relative to positive
mode. Here we demonstrate that the lower charged protein complex anions,
activated by SID in an ultrahigh mass range Orbitrap mass spectrometer, fragment
in a manner consistent with their solved structure, hence providing
substructural information. Negative mode ionization in ammonium acetate offers
the advantage of charge reduction without the peak broadening associated with
solution phase charge reduction additives and provides direct structural
information, when coupled with SID.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
0
References
0
Citations
NaN
KQI