Disrupting Biofilms: The Aftermath of Bacterial Release and Reformation

Authors: Dylan Adams, Whitni Redman, Patrick Moran

SUNY Campus: Binghamton University

Presentation Type: Poster

Location: Old Union Hall

Presentation #: 34

Timeslot: Session A 9:00-10:00 AM

Abstract: Biofilms are clusters of bacteria encased in a protective extracellular polymeric matrix (EPS) and account for 85% of all bacterial infections, including chronic wounds. Current treatments, such as antibiotics and physical debridement, are often painful and ineffective. Current work has shown exogenous cues (cis-DA, glutamate, SNP) and EPS degrading enzymes (alpha-amylase) induce bacterial release from biofilms, improving antibiotic clearance. To better understand the behavior and virulence of biofilms and released cells following a dispersion event, we investigated the recovery of biofilms and the reformation of a biofilm from released cells after treatment. We first conducted a growth curve for Pseudomonas aeruginosa with dispersion cues and enzymes to ensure bacterial growth was unaffected. Biofilms were grown using a 24-well plate assay and treated with glutamate, cis-DA, SNP, and the EPS degrading enzyme alpha-amylase, to release cells from the biofilm. Released cells were removed and inoculated in new wells, while remaining biofilms were replenished with nutrient media for recovery. Recovery and reformation was assessed at 24, 48, and 72 hours. The effectiveness of biofilm recovery and reformation was determined using crystal violet staining to measure biomass at an OD 570 nm. In 24 hour reformation biofilms, SNP treated biofilms had the greatest biomass, while Cis-DA and the control had the least. In both 48 hour recovered and reformed biofilms, SNP and Glutamate exhibited the greatest biomass, while Cis-DA and Alpha-amylase showed significantly less.