Research Projects

Our long-term goal is to develop efficacious strategies to combat multidrug-resistant (MDR) pathogens, a growing threat, particularly in healthcare settings. One attractive anti-microbial approach is quorum sensing (QS) inhibition, an anti-virulence strategy fundamentally different from current traditional therapies. Pseudomonas aeruginosa (PA) is a notorious multidrug-resistant (MDR) pathogen, categorized as an ESKAPE pathogen, that poses significant clinical challenges. It has intricate quorum sensing (QS) networks that govern both acute and chronic infection processes, as well as systemic infections (1-18). PA relies on at least three major QS systems LasR, MvfR (PqsR), and RhlR which are interconnected and regulated by specific transcription factors (5,8,11,17,18). These QS networks not only influence PA's pathogenicity but also modulate its interactions with the host. Although their relevance in pathogenesis has been recognized, most studies to uncover the mechanisms underlying the importance of QS in infection are performed in vitro, limiting relevance to the human environment during infection. To combat PA infections, it is pivotal to understand the functions and interrelationships of the QS systems and the consequences of their disruption in a dynamic host environment. Thus, the immediate goal of this application will fill existing gaps by addressing three fundamental questions in a dynamic and human-relevant host environment: 1) What are the regulatory relationships and functions of the PA 2) How do anti-QS therapies impact infection severity and QS regulatory interactions in multidrug resistant PA 3) identifying novel therapeutic targets, and developing anti-quorum sensing (anti-QS) therapies. These questions will not only fill existing gaps but will also provide crucial answers to long-standing questions about the anti-virulence approach strategy and the role of lasR mutations in PA virulence. The study will employ a multi-disciplinary approach involving: (1) dual RNA sequencing (Dual RNAseq) to capture concurrent host and bacterial gene expression during infection, providing insights into regulatory relationships; (2) immuno-metabolic profiling to analyze shifts in host and bacterial metabolism and immune responses using GC-MS and LC-MS; (3) genome-wide CRISPR-Cas9 screening to discover essential host and bacterial genes that could serve as therapeutic targets; and (4) high-throughput screening of natural and synthetic compounds to identify and optimize lead anti-QS candidates for in vivo validation. The successful completion of this research will advance the field by providing new insights into host-pathogen dynamics and offering promising avenues for developing novel anti-MDR therapies, including potential anti-QS agents that circumvent traditional antibiotic pathways.