> Thesis Defense Announcement > To: The George Mason University Community > > *Candidate: Sarah Hamer > Program: Master of Science in Biology > * > *Date: Wednesday April 25, 2012 > Time: 10:00 a.m. > Place: George Mason University, Prince William campus <http://www.gmu.edu/resources/visitors/findex.html> > Bull Run Hall, Room 247 > > *Thesis Chair: Dr. Serguei Popov > Thesis Director: Dr. Myung-Chul Chung > > Title: "The S-nitrosylation of Peroxiredoxin 1 in Human Small Airway Epithelial Cells During Bacillus Anthracis Infection" > A copy of the thesis is on reserve in the Johnson Center Library, > Fairfax campus. The thesis will not be read at the meeting, but > should be read in advance. All members of the George Mason University > community are invited to attend. > > *ABSTRACT: > *Bacillus anthracis, a Gram-positive soil organism, is the causative > agent of anthrax. Although the key virulence factor of anthrax is > mediated by toxins (i.e. lethal toxin and edema toxin), it has proven > that the bacterial nitric oxide synthase (bNOS) of B. anthracis, also, > plays a role in pathogenesis. Since B. anthracis infection produced > bona fide nitric oxide that is responsible for protein modification by > S-nitrosylation, I hypothesized that bNOS-induced nitric oxide > contributes to regulation of host cell function through protein > chemical modification. The nitrosproteomic analysis using the > biotin-switch assay demonstrated that during B. anthracis infection, > peroxiredoxin 1 (Prx1) was predominantly S-nitrosylated; there was a > decrease in its peroxidase activity and an increase in its chaperone > activity, which both affect cell viability. Treatment with a nitric > oxide donor in a high hydrogen peroxide environment decreased cell > viability; while during B. anthracis there was an increase in cell > viability, presumably due to increase of chaperone activity of Prx1. > These results suggest that during B. anthracis infection, > bacteria-derived nitric oxide plays a role in oxidative or nitrosative > stress-induced epithelial responses to the pathogen in the lung. > > // > ###** > >