Figure 4.

Examples of possible modification distributions in typical mass spectra. (A) Normal distribution of modified species where small amounts of apo- (0 modifications) and fully modified species (9 modifications) exist simultaneously; (B) semi-cooperative pattern, has significant amounts of the apo-species, intermediates (1–8 modifications), and fully modified species; (C) cooperative pattern, where few intermediates exist and the spectra is dominated by the apo- and fully modified species.