Welcome to the Rajagopal Lab
In the Rajagopal lab, we utilize genetic, molecular, biochemical and proteomic approaches to study infectious diseases caused by bacteria. The human pathogens that we study are group B Streptococcus and Staphylococcus aureus. Although both GBS and S. aureus are commensal organisms, these bacteria can also become disease-causing pathogens.
GBS Hemolytic Toxin Research
Rajagopal’s previous GBS research, published in the Journal of Experimental Medicine in 2013, determined the hemolytic toxin found in GBS was not a protein, as previously believed, but a different cell structure known as a lipid. The finding may prevent the development of a vaccine for GBS, because the molecular structure of lipids prevents the toxin from being inactivated by antibodies – the traditional way that vaccines neutralize toxins made of protein molecules. More recently, the group has shown that the GBS hemolytic toxin destroys neutrophils and evades neutrophil extracellular traps in the placenta leading to fetal injury and preterm labor (Sci Immunol 2016;1(4):aah4576).
See also the article and video Study shows how Group B strep foils defenses in pregnancy in the October 2016 issue of UW Health Sciences’ NewsBeat.
Current Research Projects
Current research projects on group B Streptococcus are focused on understanding how the pathogen migrates through different host niches during infections. Research includes identifying the environmental cues/signals that are sensed by the pathogen for regulation of toxins and other virulence factors. Our studies on S. aureus are focused on elucidating factors that regulate antibiotic resistance and virulence of the pathogen. We are also investigating how mutations in host signaling pathways affect disease susceptibility to S. aureus. This is particularly relevant as patients with genetic disorders such as Jobs syndrome and chronic granulomatous disease (CGD) are prone to recurrent and life-threatening infections due to S. aureus.
We hope that a greater understanding of the molecular mechanisms involved during bacterial pathogenesis will enable us to identify novel compounds that can be used to treat these bacterial infections.
Dr. Rajagopal is an associate professor in the Department of Pediatrics, Division of Infectious Disease at the University of Washington. She has adjunct faculty appointments in the Departments of Microbiology and Global Health at the University of Washington. She is also a full faculty member of the Molecular and Cellular Biology PhD program of the University of Washington and a course coordinator of the PABIO 551 program in the Interdisciplinary Pathobiology PhD program.
Rajagopal is a member of the Center for Global Infectious Disease Research at Seattle Children's Research Institute, where her laboratory is physically located. She is an internationally recognized expert on the role of novel signaling pathways in Gram-positive pathogens.
Funding for her research is in part supported by the NIAID-NIH.