Table 1. Numbers of Target and Identified PTMs Using the G-PTM Search Strategy. These Data Are for Human Jurkat Cells; The Analogous Data for Mouse Are in Supplemental Table S5. The “Database PTM Positions” Column Shows That a Total of 22 540 Residue Positions from 104 PTM Types Were Included in the Human UniProt XML File. The G-PTM Search Identified Peptides with Modifications at 1969 of Those Positions, across the 26 Observed PTM Types Listed Here (See Supplementary Table S2 for Entire List). ^aETA Is an Abbreviation for “Ethanolamine”.