Table 1. Summary of the Information Provided by the Tested Fragmentation Strategies on Intact Precursors or Alkali Metal Adducts of Tyrosine-Sulfopeptides (sY) or Tyrosine-Phosphopeptides (pY) by nanoHPLC-MS/MS in the Positive Ionization Mode.
| intact
precursors |
alkali metal adducts |
|||
|---|---|---|---|---|
| pY | sY | pY | sY | |
| CID | sequence/localization | SO3 neutral lossb | sequence/localization | SO3 neutral lossb |
| HCD | sequence/localization | sequence | sequence | |
| ETD | sequence/localization | SO3 neutral lossb | sequence/localizationa | sequence/localizationa |
| ETciD | sequence/localization | SO3 neutral lossb | sequence/localizationa | sequence/localizationa |
| EThcD | sequence/localization | sequence | sequence/localizationa | sequence/localizationa,b |
a
Applies only to higher charge states.
b
Allows discrimination between phosphopeptides and sulfopeptides