Native top-down electrospray ionization-mass spectrometry of 158 kDa protein complex by high-resolution Fourier transform ion cyclotron resonance mass spectrometry.

ABSTRACT: Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) delivers high resolving power, mass measurement accuracy, and the capabilities for unambiguously sequencing by a top-down MS approach. Here, we report isotopic resolution of a 158 kDa protein complex, tetrameric aldolase with an average absolute deviation of 0.36 ppm and an average resolving power of ~520 000 at m/z 6033 for the 26+ charge state in magnitude mode. Phase correction further improves the resolving power and average absolute deviation by 1.3-fold. Furthermore, native top-down electron capture dissociation (ECD) enables the sequencing of 168 C-terminal amino acid (AA) residues out of 463 total AAs. Combining the data from top-down MS of native and denatured aldolase complexes, a total of 56% of the total bac

SUBMITTER: Li H 

PROVIDER: S-EPMC3908771 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature