Simultaneous Identification and Quantification of Nitrosylation Sites by Combination of Biotin Switch and ICAT Labeling - Plant Proteomics: Methods and Protocols - page 590

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ICAT-C-ICAT-C:13C(9)
SILE Labels

Fig. 2 ICAT labeling of endogeneous nitrosothiols. A saline stress was applied on A . thaliana cells and nitrosyl-
ated proteins were labeled (ICAT-13C(9)). In parallel, proteins from control cells were labeled with (ICAT-
12C(9)) and the two samples were mixed after labeling. ( a ) Example of a peptide pair from Arabidopsis Blue
Copper protein (AT5G20230), separated by 3 Th due to charge state ( z = 3). ( b ) The ratio between the two peak
intensities gives a relative quantitation of the peptides abundance under the two conditions

Fig. 3 MS/MS spectrum for an identifi ed nitrosylated peptide