report the real time description of the OCPo-to-OCPr transition
by using native MS, an emerging approach that allows for
protein oligomerization-state analysis under nondenaturing
conditions,18,19 as well as for nonprotein cofactor stoichiometry
analysis.20 When combined with ion-mobility MS (IM-MS),
this approach can be used to probe structural transitions of
protein complexes in their near-native states.21,22