Kelsi L. Anderson, Ph.D.
Mary O'Riordan, Ph.D.
Intracellular pathogens exploit a variety of host factors enabling them to proliferate and cause an array of infections. Listeria monocytogenes is an intracellular pathogen that is able to escape the bacteriocidal environment of the host cell vacuole into the cytosol where it can replicate and then spread to neighboring cells. L. monocytogenes ' ability to escape from host vacuoles is facilitated by the pore forming toxin listeriolysin O (LLO). Although LLO is known to be activated in response to the acidic environment of pathogen-containing vacuoles (PCV), the model of pH activation does not completely explain LLO-dependent escape. Preliminary studies from our laboratory demonstrate that LLO-mediated vacuole escape is also regulated by the cystic fibrosis transmembrane conductance regulator (CFTR), a well-characterized chloride transporter. We hypothesize that chloride flux facilitates L. monocytogenes' ability to escape from PCV by modulating LLO activity. Chloride flux may mediate vacuole escape by one of two ways: vacuole acidification or by transiently altering the vacuolar salt concentration which, in turn, regulates LLO. Our work has expanded significance in that CFTR-mediated chloride flux may provide essential factors to vacuolar pathogens which facilitate their ability to survive in these otherwise nutrient-limited compartments.
Shah RD, Anderson KL , Rapoport M, Ferreira A. Estrogen-induced changes in the microtubular system correlate with a decreased susceptibility of aging neurons to beta amyloid neurotoxicity. Mol Cell Neurosci. 2003 Oct; 24(2):503-16.
Anderson KL and Ferreira A. alpha1 Integrin activation: a link between beta-amyloid deposition and neuronal death in aging hippocampal neurons. J. Neurosci. Res. 2004 Mar 1; 75(5):688-97.
Anderson KL , Paganoni S, Ferreira A. Differential subcellular localization of Ror tyrosine kinase receptors in cultured astrocytes. Glia. 2004 May; 46(4):456-66.
Roberts CJ, Anderson KL , Murphy E, Projan SJ, Mounts W, Hurlburt B, Smeltzer M, Overbeek R, Disz T, and Dunman PM. Characterizing the effects of the Staphylococcus aureus virulence factor regulator, SarA, on log-phase mRNA half-lives. J Bacteriol. 2006 Apr; 188(7):2593-603.
Anderson KL, Roberts CJ, Disz T, Vonstein V, Overbeek R, Olson PD, Projan SJ, and Dunman PM. Characterization of the Staphylococcus aureus heat-shock, cold-shock, stringent, and SOS responses and their effects on log-phase mRNA turnover. J. Bacteriol. 2006 Oct; 188(19):6739-6756.
Torres VJ, Stauff DL, Pishchany G, Bezbradica JS, Gordy LE, Iturregui J, Anderson KL , Dunman PM, Joyce S, and Skaar EP. A Staphylococcus aureus regulatory system that responds to host heme and modulates virulence. Cell Host Microbe. 2007 Apr 19; 1(2):109-19.
Corbin BD, Seeley EH, Raab A, Feldmann J, Miller MR, Torres VJ, Anderson KL , Dattilo BM, Dunman PM, Gerads R, Caprioli RM, Nacken W, Chazin WJ, and Skaar EP. Metal chelation and inhibition of bacterial growth in tissue abscesses. Science . 2008 Feb 15; 319(5865):962-65.
Stauff DL, Bagaley D, Torres VJ, Joyce R, Anderson KL , Kuechenmeister LJ, Dunman PM, and Skaar EP. Staphylococcus aureus HrtA is an ATPase required for protection against heme toxicity and prevention of a transcriptional heme-stress response. J. Bacteriol. 2008 May; 190 ( 10 ): 3588-96.
Kuechenmeister LJ, Anderson KL , Morrison JM, and Dunman PM. The use of Molecular Beacons to Directly Measure Bacterial mRNA Titers and Transcript Degradation. J Microbiol Methods . 2008 Oct 25. [Epub ahead of print].
Anderson KL and Dunman PM. Messenger RNA turnover processes in Escherichia coli, Bacillus subtilis, and emerging studies in Staphylococcus aureus . Intl. J Microbiol. In press.
2004-2007 - University of Nebraska Medical Center Graduate Studies Fellowships
2006 - University of Nebraska Medical Center Regents Tuition Fellowship
2007 - Leading Student Presentation; 51 st Annual Wind River Conference on Prokaryotic Biology
2007 - First Place Graduate Student Research Seminar; University of Nebraska Medical Center Pathology & Microbiology Department
2007-2008 - American Heart Association Heartland Affiliate Predoctoral Fellowship
2008 - Sigmi Xi Award of Merit Graduate Student Presentation; 39 th Annual Midwest Student Biomedical Research Forum
2008 - First Place Graduate Student Research Seminar; University of Nebraska Medical Center Pathology & Microbiology Department