Date of Award
Fall 2023
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Microbiology
First Advisor
Kazmierczak, Barbara
Abstract
Antimicrobial resistance is a looming threat that reflects the remarkable capacity of bacteria to adapt and change in response to selective pressures. The versatile pathogen P. aeruginosa is a model case---already intrinsically resistant to many antibiotics, it can establish decades-long chronic infections, during which it evolves to survive antimicrobial treatment and evade host defenses. Many changes occur on its cell surface, a key location for both virulence and antibiotic resistance, but our technologies for studying these adaptive phenotypes are limited. Here we combined phage display with high-throughput DNA sequencing to create a high throughput, highly multiplexed technology for surveying bacterial cell surfaces. We performed phage display panning on hundreds of pairs of bacterial genotypes and used sequencing data to analyze the dynamics of the phage display selection process. We showed that these datasets capture important biological information about the surfaces of the cells under study. We discovered dozens of nanobodies that recognize key P. aeruginosa virulence factors, including determinants of antimicrobial resistance, in their native conformations on live cells; these antibodies have numerous potential applications in diagnostics and therapeutics. We propose that this technology---"Phage-seq"---enables a new paradigm for studying the bacterial cell surface by identifying and profiling many surface features in parallel. The techniques we have developed will allow us to better understand how bacteria adapt to life in the human host and to antimicrobial treatment.
Recommended Citation
Grun, Casey, "Bacterial cell surface characterization by phage display coupled to high-throughput sequencing" (2023). Yale Graduate School of Arts and Sciences Dissertations. 1376.
https://elischolar.library.yale.edu/gsas_dissertations/1376
