Analysis of Post Translational Modifications by Mass Spectrometry

The dissertation is composed of three projects, connected by the common goal of detection of post translational modifications on proteins by tandem mass spectrometry. From beginning to end, each of the projects is very different from the next, sampling the field of protein mass spectrometry.

The first project described in this dissertation is a proteomic based project at its core. Tryptic peptides, enriched for arginine methylation, are analyzed from cells treated under different conditions. A search algorithm is used to prioritize results; ultimately two spliceosome proteins are manually validated across all samples to better understand the constraints of the method. The second project is a detailed characterization of an acidic post translational modifications on larger peptide fragments from a histone chaperone protein, Nucleosome Assembly Protein 1-like. The final project applies a state-of-the-art technique for intact protein analysis and applies it to a complex biological sample, Nucleoplasmin purified from Xenopus eggs.