Mass spectrometry reflects key aspects of copper-amyloid β chemistry.

Mass spectrometry is a powerful method to study protein complexes; however, biochemical reactions are typically beyond the scope of MS studies. Here, we have studied the gas-phase redox chemistry of the [copper(II) – amyloid β] complex and show that the sequence-dependence of this chemistry reflects key aspects of the known in vitro behaviour of different variants of the peptide. [ABSTRACT FROM AUTHOR]