Amanda Brosnahan

E-mail: helv0010@umn.edu

Thesis Advisor: Pat Schlievert

Year entered: 2004

Degrees received:
B.S., Microbiology, University of Minnesota, Minneapolis, MN, 2004

Honors and Awards:

• 3M Graduate Fellowship (2004-2008)
• ASM Student Travel Grant (2008)

Thesis research:
The focus of my research is the interaction of streptococcal and staphylococcal superantigens with the vaginal mucosa. Specifically, we are interested in how superantigens penetrate the mucosa in order to cause the systemic symptoms seen in toxic shock syndrome. Using porcine vaginal epithelium, we have been able to show that hemolysins also secreted by the bacteria act to disrupt the mucosa to augment the penetration of superantigens. Another aspect of my research is to examine the cytokine production by epithelial cells in response to bacterial exotoxins. By examining a specific region that is conserved among all superantigens, we have been able to narrow down which amino acid residues are responsible for interacting with epithelial cells to cause inflammation. Gaining a better understanding of how superantigens interact with and move through the mucosa may provide insights into how to target the toxins before they penetrate the surface.

Publications:

• Strandberg, K.L., A.J. Brosnahan, and P.M. Schlievert. 2007. Staphylococcal and streptococcal toxic shock syndrome. In: Encyclopedia of Science. Brown Reference Group, London, UK. In press.

• Schlievert, P.M., L.C. Case, K. A. Nemeth, C.C. Davis, Y. Sun, W. Qin, F. Wang, A. J. Brosnahan, J.A. Mleziva, M.L. Peterson, and B.E. Jones. 2007. Alpha and beta chains of hemoglobin inhibit production of Staphylococcus aureus exotoxins. Biochemistry 46:14349-14358.