Bacteria implement a number of proteins that promote colonization of new environments. In order to establish complete colonization, supplementary proteins facilitate evasion of host cell defenses and acquisition of essential nutrients. Bacteria commonly recruit protein secretion systems to establish efficient and effective host cell invasion and nutrient acquisition, and the TPS pathway is the most commonly implemented bacterial protein secretion pathway. Our prior NSF-funded studies determined the crystal structure of hemolysin A (HpmA), a TPS member protein from Proteus mirabilis. This truncated form of HpmA adopted a unique beta-helix (beta-HP) structure, resisted high temperature unfolding and facilitated cooperative activity. Beyond HpmA and the TPS pathway, the alpha-HP structure has been linked to a number of scientific areas including enzymes, bacterial and viral virulent proteins, hormones, and transmissible and non-transmissible neurological infection. The overarching goal of this research relates beta-HP structure to TPS pathway function. For this project, a truncated version of hemolysin A will be implemented as a model beta-HP. Specifically, the project is focused upon factors affecting the stability and functionality of hemolysin A. A number of biophysical and high-resolution imaging techniques will be conducted and focused upon delineating factors affecting the stability and functionality of hemolysin A, a noted TPS member and beta-HP. Ultimately, this project aims to extend our understanding of beta-HP structure and TPS function as related to bacterial proliferation.
Broader Impacts. All aspects of the project will be conducted in a collaborative and hypothesis driven research environment with undergraduate (UG) students. Within this collaborative environment UG research students will design, conduct and interpret experiments, and assemble and present the data in context with primary literature. UG students will present their data and results in both oral formats at regional and national meetings, as well as in written peer-reviewed publication format. Ultimately, this research environment allows students to extend the current body of scientific knowledge, while broadening their educational experience beyond the classroom. The PI has a long history of dedication and excellence in mentoring undergraduate research students. Former students have continued their studies at top-tier Ph.D. programs, such as Baylor University, University of Michigan, University of Minnesota, University of Wisconsin-Madison, and Yale University. Thus, the primary broader impact is to promote teaching and learning, while extending scientific understanding and literacy. The PI will continue to integrate science and research into local K-12 classrooms, include high school students and educators in the research lab, partner with educators to develop new means of learning, and involve undergraduate students in K-12 activities. In addition, the PI will continue to maintain established collaborations with outside institutions, offer local and national science presentations, and publish findings in a variety of media. Finally, the PI will partner with the McNair Program at UW-L to involve qualified underrepresented groups in scientific research. The societal benefits of the project include increased scientific literacy, increased numbers of students entering graduate school, and additional training for high-school educators and students.
