Date of Award


Document Type


Degree Name

Master of Science (M.S.)


Biological Sciences

First Advisor

Eric Thomas

First Committee Member

Jerry Tsai

Second Committee Member

Melanie Felmlee


Defensive mechanisms vary widely in the animal kingdom ranging from physical defenses like spines to chemical defenses such as toxins. Toxins in these secretions and tissues can fluctuate from enzymes to lipids to uncharacterized chemicals. Next generation -omics technology and mass spectrometry are extremely important in analyzing these samples because of their ability to distinguish minute amounts of toxic substance within a complicated sample. The goal of this experiment was to look at secretions and tissues from Corydoras sterbai. All samples in this study were proteolyzed using a mixture of Trypsin and Lys-C, fractionated, and run through nanoLC-MS/MS analysis using an Orbitrap Fusion™ Tribrid™ mass spectrometer. Using guanidine hydrochloride as a denaturant, a total of 420 database peptide matches were discovered in the secretions and up to 777 database peptide matches among the tissues. Proteins of interest found in both the secretion and in the hypothesized gland include members of the prostaglandin synthesis pathway, phospholipases, and peroxiredoxins. It is theorized that C. sterbai uses its serrated rays in addition to these proteins to defend themselves from would be predators.