Date of Award
Dr. Ruth Plymale
Dr. Sara Hubbard
Dr. Matt Douglass
Antimicrobial peptides (AMPs) have been a major research focus due to their potential to combat a variety of human pathogens. Our laboratory has identified several novel peptides that display significant antifungal activity. The effectiveness of these peptides in vitro has been promising; however, it has been shown that physiological concentrations of various salts along with other conditions are inhibitory to peptide activity. To further explore the inhibitory effects of these salts, a new assay was developed whereby we can observe the effects of various salts on the peptide killing activity. For our studies, we employed several clinical isolates of Candida species to evaluate the killing activity of peptides in the presence of physiologically relevant salts at varying concentrations. By adding the salts individually, we are able to examine the inhibitory effect of each. When compared to other assays, the new assay requires less time and resources by allowing us to test the AMPs under numerous conditions simultaneously. After testing the AMP, we determined that CaCl2, MgSO4, NaCl, and KCl are all inhibitory to peptide killing activity at varying degrees. In addition, we discovered that circularization or hexanoic acid modification of the peptide bypasses the inhibition of salts. Our long term goal is to modify the peptides in a way that will allow for their use in vivo.
Walter, Dustin, "Understanding a Possible Wonder Drug: A Radial Diffusion Assay for the Rapid Evaluation of Antimicrobial Peptides" (2015). Honors Theses. 177.