Chemistry, Department of


Date of this Version

Spring 4-2015


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Chemistry, Under the Supervision of Professor Eric D. Dodds. Lincoln, Nebraska: April 2015

Copyright (c) 2015 Venkata Karthik Kolli


This thesis begins with an overview of the state-of-the-art in tandem mass spectrometry (MS/MS) analysis of glycopeptides. In this introduction, the primary focus is on utilization of different ion dissociation techniques for MS/MS to obtain structural information of N-glycopeptides. This includes a discussion of the importance of complementary MS/MS methods to attain complete structural characterization of N-glycopeptides. Emerging methods involving the use of a single ion dissociation technique for complete glycopeptide connectivity analysis were also presented. Next, the application of collision-induced dissociation (CID) to provide both amino acid sequence and monosaccharide connectivity for model N-glycopeptides was discussed in detail. Implementation of varying collision energies to generate energy-resolved breakdown curves suggested unique ranges of collision energies allowed glycan and peptide fragments to be obtained. An online collision energy modulation was demonstrated to allow both glycan and peptide fragments to be gathered in a single CID spectrum. Finally, the role of proton mobility in dictating the energy-resolved CID behaviors of N-glycopeptides was examined. Energy-resolved CID studies in the context of different precursor ion proton mobilities suggested the possibility that peptide and glycan cleavage products could be deliberately accessed at predictable collision energies.

Advisor: Eric D. Dodds