Inhibitors of anthrax pathogenesis
Abstract
Bacillus anthracis is the causative agent for the disease anthrax and is an important pathogen today as a result of bioterrorism. The disease anthrax is directly linked to two exotoxins, lethal toxin and edema toxin. The combination of protective antigen (PA) and lethal factor (LF) make up lethal toxin (LT), while PA and edema factor (EF) comprise edema toxin (ET). Although ET has been shown to be important for anthrax pathogenesis, the current work focuses on inhibiting LT by specifically inhibiting within the Lethal Toxin Intoxication Pathway (LTIP). In order to identify inhibitors of anthrax pathogenesis, a medium-throughput cell based screen of the LOPAC 1280 library of pharmacologically active agents (Sigma) was performed that lead to the identification of 30 compounds that rescued cells from anthrax lethal toxin-mediated death. IC50 assays were performed, and the most potent compounds were identified and further evaluated. A Western blot focusing on MEK2, a lethal factor cellular substrate, was then used to narrow down the target of inhibition to within the LTIP (steps of toxin cell entry or LF), or outside the LTIP (steps leading to apoptosis/necrosis). Secondary assays were then performed to identify specific inhibitors of LF, the endoprotease furin, and PA oligomerization. Analogs of these inhibitors were then synthesized to identify structural elements that were important for activity.
Degree
Ph.D.
Advisors
Chmielewski, Purdue University.
Subject Area
Biochemistry|Organic chemistry
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