Physical Sciences and Mathematics Commons^™

Analysis Of Structural Stability Of Human Prosecretory Mitogenic Lacritin By Circular Dichroism, Anna P. Desmarais, Casey Q. Ramirez Cortes

Senior Honors Projects, 2010-2019

Purpose: Lacritin is a human tear glycoprotein that has high thermal stability. When cleaved, lacritin has antimicrobial activity resulting from the C-terminus amphipathic alpha helical region. The alpha helices contain three salt bridges; ionic bonds between neighboring oppositely charged amino acids. The purpose of this research was to investigate the hypothesis that the salt bridges within the alpha helices contribute to the high thermal stability.

Methods: To determine the role of salt bridges in the thermal stability of lacritin, point mutants were prepared for each salt bridge by site directed mutagenesis that replaced the oppositely charged amino acids with serine. …