Figure 13.
UV photodissociation of two epimeric peptides: (a) [IQTGLDATHAER + H]+ and (b) [IQTGLDATHAER + 2H]2+. The d-form shows abundant −56 Da loss from Leu for both charge states. The downward arrow indicates the selected precursor ion. Reproduced with permission from ref 125. Copyright 2012 American Chemical Society.