Metabolomic insights into Pseudomonas aeruginosa behavior, secretome, and biofilm development using mass spectrometry imaging

Since the early twentieth century, antibiotics have been employed to treat bacterial infections, but bacteria have constantly evolved mechanisms that combat antibiotic treatment. These evolved mechanisms, including biofilm formation and antibiotic-inactivating enzymes, have been studied as potential factors for antibiotic resistance. Pseudomonas aeruginosa, also selected to be one of the multidrug-resistant ESKAPE pathogens, is a Gram-negative nosocomial bacterium responsible for about 7% of all hospital-acquired infections. P. aeruginosa is often referred to as an opportunistic pathogen, known to infect patients with low immunity, such as those who have been diagnosed with cystic fibrosis (CF), cancer, and other immunocompromising diseases. P. aeruginosa is the model organism for biofilm studies due to its robust understanding of the production of biofilm. During biofilm production, P. aeruginosa secretes secondary metabolites into the biofilm matrix. While the characterization of some of these molecules has increased our understanding of biofilm initiation, production, and maturation processes, some key aspects of these processes and secondary metabolite functions, such as some environmental conditions required for secretion and the effects of external small molecule stressors, have yet to be elucidated. To illuminate these understudied factors, my work explores the impact of small-molecule perturbations on the growth, biofilm production, and secretion profile of three molecular types. Specifically, the impact D-amino acids, bio-metals, and rhamnolipid congeners are explored on the growth, biofilm production, and secretion profile of P. aeruginosa in vitro, ex vivo lung tissues, and abiotic surfaces. These studies used mass spectrometry imaging (MSI), a chemical imaging technique used for its functionality in studying the spatial distribution of molecules on a two-dimensional surface. This technique is a label-free method suitable for biological samples due to its ability to analyze complex samples with high sensitivity and has been commonly used to study biofilm models on a variety of bacterial samples. An improved understanding of the effects these small molecules have on the pathogenicity and biofilm development of P. aeruginosa may have broader implications in developing treatments for infection by biofilm-producing organisms.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Rosado-Rosa, Joenisse Marie

Contributors dc:contributor

• Sweedler, Jonathan V.
• Sweedler, Jonathan V
• Hergenrother, Paul J
• van der Donk, Wilfred A
• Chan, Jefferson

• Metabolomics
• Biofilm
• Pseudomonas Aeruginosa
• Mass Spectrometry Imaging
• Quorum Sensing
• Bacterial Vaccines
• Protein Engineering
• Nad+
• Swarming
• Quinolones
• Phenazines
• Rhamnolipids

Statement dc:rights

• Copyright 2025 Joenisse Marie Rosado-Rosa

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/130169

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F130169