Uncovering the phenotypic and transcriptional characteristics of biofilm-released cells in <i>Pseudomonas aeruginosa</i>

Jason Li; Larry Ayiku; Benjamin Larson; Agam Patel; Dylan Adams; Patrick Moran; Samantha Burgan; Esha Shah; Anthony Bruno; Jaclyn Printz; Tevin Flom; Whitni K. Redman; Jason Li; Larry Ayiku; Benjamin Larson; Agam Patel; Dylan Adams; Patrick Moran; Samantha Burgan; Esha Shah; Anthony Bruno; Jaclyn Printz; Tevin Flom; Whitni K. Redman

doi:10.3934/microbiol.2026031

AIMS Microbiology

2026, Volume 12, Issue 3: 718-741. doi: 10.3934/microbiol.2026031

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Research article

Uncovering the phenotypic and transcriptional characteristics of biofilm-released cells in Pseudomonas aeruginosa

1.
Department of Biological Sciences, Binghamton University, Binghamton, NY, United States
2.
First-year Research Immersion Program, Binghamton University, Binghamton, NY, United States
These three authors contributed equally.

Received: 12 July 2026 Revised: 18 September 2026 Accepted: 29 September 2026 Published: 30 September 2026

Pseudomonas aeruginosa is a prominent biofilm-forming pathogen associated with chronic infections that are difficult to eradicate due to the protective biofilm matrix. Inducing biofilm dispersion has emerged as a potential therapeutic strategy. Although researchers have compared selected biofilm dispersion mechanisms, the characteristics of cells generated by mechanistically distinct release strategies, particularly enzymatic matrix degradation, remain uncharacterized. In this study, we compared P. aeruginosa cells released from biofilms using four distinct dispersion mechanisms: An external signaling molecule (cis-2-decenoic acid; cis-DA), a nutrient cue (glutamate), an environmental toxin (sodium nitroprusside; SNP), and a matrix-degrading enzyme (amylase). Released cells exhibited distinct antibiotic susceptibility, attachment, and gene expression depending on the release mechanism. Glutamate-released cells exhibited greater tobramycin tolerance and attachment, whereas glutamate and amylase-released populations exhibited differences in the expression of selected genes. Additionally, the release mechanism influenced subsequent biofilm recovery and reformation, and cis-DA significantly enhanced tobramycin-mediated killing of mature biofilms. Collectively, these findings demonstrate that the mechanism used to induce release may influence subsequent bacterial behavior and antibiotic susceptibility. These findings highlight the importance of considering release mechanism when developing dispersion-based strategies for treating biofilm-associated infections.
- Pseudomonas aeruginosa,
- biofilm dispersion,
- biofilm-released cells,
- gene expression,
- antibiotic tolerance,
- bacterial attachment,
- biofilm reformation
Citation: Jason Li, Larry Ayiku, Benjamin Larson, Agam Patel, Dylan Adams, Patrick Moran, Samantha Burgan, Esha Shah, Anthony Bruno, Jaclyn Printz, Tevin Flom, Whitni K. Redman. Uncovering the phenotypic and transcriptional characteristics of biofilm-released cells in Pseudomonas aeruginosa[J]. AIMS Microbiology, 2026, 12(3): 718-741. doi: 10.3934/microbiol.2026031

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Abstract

Pseudomonas aeruginosa is a prominent biofilm-forming pathogen associated with chronic infections that are difficult to eradicate due to the protective biofilm matrix. Inducing biofilm dispersion has emerged as a potential therapeutic strategy. Although researchers have compared selected biofilm dispersion mechanisms, the characteristics of cells generated by mechanistically distinct release strategies, particularly enzymatic matrix degradation, remain uncharacterized. In this study, we compared P. aeruginosa cells released from biofilms using four distinct dispersion mechanisms: An external signaling molecule (cis-2-decenoic acid; cis-DA), a nutrient cue (glutamate), an environmental toxin (sodium nitroprusside; SNP), and a matrix-degrading enzyme (amylase). Released cells exhibited distinct antibiotic susceptibility, attachment, and gene expression depending on the release mechanism. Glutamate-released cells exhibited greater tobramycin tolerance and attachment, whereas glutamate and amylase-released populations exhibited differences in the expression of selected genes. Additionally, the release mechanism influenced subsequent biofilm recovery and reformation, and cis-DA significantly enhanced tobramycin-mediated killing of mature biofilms. Collectively, these findings demonstrate that the mechanism used to induce release may influence subsequent bacterial behavior and antibiotic susceptibility. These findings highlight the importance of considering release mechanism when developing dispersion-based strategies for treating biofilm-associated infections.

Acknowledgments

This work was supported by the First-year Research Immersion Program at Binghamton University, the Harpur's Edge Award and Undergraduate Research Award from the External Scholarship and Undergraduate Research Center at Binghamton University. The authors acknowledge the First-year Research Immersion Program for providing laboratory space, equipment, and institutional resources that made this work possible. The authors would also like to thank Rachel Washburn from the University of Kentucky for reviewing this manuscript prior to submission.

Conflict of interests

All authors declare no financial or non-financial competing interests.

Author contributions

Larry Ayiku: Validation, Investigation, Writing-Original Draft, Writing-Review & Editing. Jason Li: Validation, Investigation, Writing-Original Draft, Writing-Review and Editing. Benjamin Larson: Validation, Investigation, Writing-Original Draft, Writing-Review and Editing. Agam Patel: Validation, Investigation, Writing-Original Draft, Writing-Review and Editing. Dylan Adams: Validation, Investigation, Writing-Original Draft, Writing-Review and Editing. Patrick Moran: Validation, Investigation, Writing-Original Draft, Writing-Review and Editing. Samantha Burgan: Validation, Investigation, Writing-Original Draft, Writing-Review and Editing. Esha Shah: Validation, Investigation, Writing-Original Draft, Writing-Review and Editing. Anthony Bruno: Validation, Investigation, Writing-Original Draft. Tevin Flom: Conceptualization, Validation, Investigation, Writing-Original Draft, Visualization, Writing-Review and Editing. Jaclyn Printz: Validation, Investigation, Visualization, Writing-Review and Editing. Whitni K. Redman: Conceptualization, Methodology, Validation, Formal analysis, Investigation, Resources, Writing-Original Draft, Writing-Review and Editing, Visualization, Supervision, Project administration, Funding acquisition.

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