By maintaining intact multi-protein complexes in the gas-phase, native mass spectrometry provides their molecular weight with very good accuracy compared to other methods (typically native PAGE or SEC-MALS) (Marcoux and Robinson, Structure 21:1541-1550, 2013). Besides, heterogeneous samples, in terms of both oligomeric states and ligand-bound species can be fully characterized. Here we thoroughly describe the analysis of several oligomeric protein complexes ranging from a 16 = kDa dimer to a 801-kDa tetradecameric complex on different instrumental setups.
Keywords: Noncovalent mass spectrometry; Oligomeric states; Stoichiometry; Structural mass spectrometry; Subcomplexes.