Differentiation of Symmetric/Asymmetric Dimethylated Arginine-containing Peptides using MALDI Tandem Mass Spectrometry

摘要

Differentiation of symmetric- and asymmetric-dimethylation of arginine using MS/MS on a novel MALDI-TOF-TOF Characteristic losses from the precursor and selected fragments permitted differentiation of the two forms of dimethylation. MALDI-TOF-TOF MS/MS spectra are simpler than those generated on ESI instrumentation due to the higher charge states observed as a result of the presence of multiple basic residues in the peptide sequences (previous experience, not shown). Future work will focus on application of this technique to the identification and differentiation of modified peptides from more complex samples prepared by LC fractionation prior to MALDI analysis.