Sampling, Detection, and Characterization of Endogenous Peptides

"In the past two decades mass spectrometric detection has exploded onto the scene of biological research due to the soft ionization techniques of matrix assisted laser desorption ionization (MALDI) and electro spray ionization (ESI), as evidenced by the 2002 Nobel Prize in Chemistry. Using these techniques to create gaseous ions has led to the advent of proteomic and peptidomic studies driven primarily by mass spectrometry (MS) detection. Its utility comes from coupling the soft ionization with the mass accuracy and sensitivity in MS instrumentation, along with the structural characterization available from fragmentation techniques such as collisionally induced dissociation (CID) and electron transfer dissociation (ETD). The Sweedler group has used multiple MS techniques to help unravel the complex mechanisms involved in neuronal function. The primary goal of my dissertation research is to use MS coupled to sampling and separation strategies to identify and characterize peptides in complex systems. First, I will demonstrate its usefulness in elucidating the sequences and post-translational modifications (PTMs) present in the neurochemical toxins of a cone snail. The biological specificity and deadly potency of cone snail venom peptides has inspired their study in many research labs around the globe. Over 600 species of Conus exist, each having a vast array of toxins evolutionarily developed to target specific ligand and ion gated channels. Here I describe the first peptides characterized from the novel species of Conus californicus. Next, I will describe how LC-MS techniques coupled to genomic information allowed the elucidation of more than 35 neuropeptide genes in the social insect of the honey bee, Apis mellifera. The honey bee is a model organism for the study of social insects, and more specifically ""sociogenomics"". Due to the lack of neuropeptide information available for the honey bee, we sought to expand the breadth of knowledge using LC-MS and bioinformatics. Finally, I will discuss a new strategy for collection of stimulation dependent release of peptides that has been developed. With MALDI-MS detection I will demonstrates its usefulness for characterizing novel and potentially bioactive neuropeptides."

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Richmond, Timothy Alan

Contributors dc:contributor

• Sweedler, Jonathan V.

• Chemistry, Biochemistry

Language dc:language

eng

Identifier

(MiAaPQ)AAI3270008

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/84262