The Gram-negative Stenotrophomonas maltophilia is naturally found in water, soil and the plant rhizosphere, and is increasingly recognized as an important opportunistic and nosocomial infection. Despite its rising prevalence and drug resistance, there is little known about S. maltophilia pathogenesis. In this dissertation, I explored two aspects of S. maltophilia...
Symbiotic relationships involve a life-long interaction between host and bacteria, and there is much we do not understand about how these interactions are developed and maintained. During the horizontal recruitment of beneficial bacteria by hosts, a complex set of molecular signals and communication ensures specificity. On the bacterial side, these...
Cytokines made by macrophages play a critical role in determining the course of Legionella pneumophila infection. Prior, murine-based modeling indicated that the cytokine response initiated upon recognition of L. pneumophila involves a subset of Toll-like receptors, namely TLR2, TLR5, and TLR9. Using shRNA/siRNA knockdowns and subsequently CRISPR/Cas9 knockouts (KO), I...
If life exists on Mars, it likely resides in a deep subsurface environment. The Martian rocky subsurface is a primary target for the search for extraterrestrial life because it offers a stable habitat for microbial life. On Earth, the continental subsurface is a key astrobiological analog for understanding what properties...
Staphylococcus aureus (SA) is a leading cause of healthcare-associated and community-acquired infection in the United States. Despite the canonical thinking that antibodies and B cells are the main drivers of protection against extracellular pathogens, T cells are now recognized as critical players in protection against SA in multiple routes of...
Pseudomonas aeruginosa is an important gram-negative opportunistic pathogen whose large genome allows it to thrive in diverse environments. There is a wide range of phenotypic variation within the species, which can be attributed both to variation in sequences present in most isolates (the core genome) or the presence or absence...
Bacteria often coordinate virulence factors to fine-tune the host response during infection. These coordinated events can include toxins counteracting or amplifying effects of another toxin or though regulating the stability of virulence factors to remove their function once it is no longer needed. Multifunctional autoprocessing repeats-in toxin (MARTX) toxins are...
This work is composed of two separate projects that contribute to the field’s understanding of Neisseria gonorrhoeae genetics and physiology. First, I showed that N. gonorrhoeae mounts a substantial transcriptional program in response to hydrogen peroxide (HP), a prominent reactive oxygen species (ROS) encountered during infection. We measured which strain...
Herpes simplex encephalitis (HSE) is a rare and severely debilitating life-threatening disease caused by herpes simplex virus type 1 (HSV-1) infection of the human central nervous system (CNS). The severe and often fatal outcomes of HSE contrast starkly with the more frequent and largely benign consequences of herpes labialis. Whole...
Wastewater and bioreactors in wastewater treatment plants (WWTPs) are reservoirs for antibiotic resistance genes (ARGs), which can pass through treatment processes and migrate into the environment as they are released in effluent. WWTPs harbor a variety of ARGs that can be spread by horizontal gene transfer facilitated by mobile genetic...