Assessing Porcine Gastric and Trachea Mucin Antimicrobial Activity Against Pseudomonas Aeruginosa

Abstract

Mucus is present throughout the human body, lining all wet epithelia, making it a native, familiar material to the innate immune system. The biocompatibility of mucus opens the possibility for therapeutic applications. Existing research has shown that exposure to mucus triggers the downregulation of virulence genes in some bacteria species and rapidly disintegrates biofilms. The aim of this project is to test the innate antimicrobial activity of porcine gastric mucin (PGM) and porcine trachea mucin (PTM) against Pseudomonas aeruginosa. We examined the antimicrobial activity of mucins by quantifying bacteria growth and viability at numerous time points after mucin treatment. To test this hypothesis, PAO1 cultures were grown in LB broth overnight. Mucin was added to the planktonic PAO1 cultures at various concentrations, 8%, 4%, 2%, 1%, and 0.5% w/v, with each concentration tested in triplicates. At the 3 hr, 6 hr, and 24 hr timepoints after mucin addition, samples were taken from each culture, diluted, and spot-plated. The plates were grown overnight and counted the next day to calculate the colony-forming units. Preliminary results suggest that increasing mucin concentration correlates with decreased bacterial growth, as hypothesized. Additionally, PGM possibly shows a greater degree of antimicrobial effect than PTM. This research has a great potential impact. Pseudomonas aeruginosa is an opportunistic pathogen often developing antibiotic resistance making it extremely difficult to treat and a high priority for novel treatment development. Therefore, a novel treatment method against P. aeruginosa can have broad implications and improve bacterial infection treatments.