We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Biofilm disruption by an air bubble reveals heterogeneous age-dependent detachment patterns dictated by initial extracellular matrix distribution.
- Authors
Jang, Hongchul; Rusconi, Roberto; Stocker, Roman
- Abstract
Bacteria often adhere to surfaces, where they form communities known as biofilms. Recently, it has been shown that biofilm formation initiates with the microscopically heterogeneous deposition of a skeleton of extracellular polymeric substances (EPS) by individual cells crawling on the surface, followed by growth of the biofilm into a surface-covering continuum. Here we report microfluidic experiments with Pseudomonas aeruginosa biofilms showing that their "hidden" heterogeneity can affect the later dynamics of their disruption. Using controlled air bubbles as a model for mechanical insult, we demonstrate that biofilm disruption is strongly dependent on biofilm age, and that disruption to early-stage biofilms can take the shape of a semi-regular pattern of ~15 µm diameter holes from which bacteria have been removed. We explain hole formation in terms of the rupture and retreat of the thin liquid layer created by the long bubble, which scrapes bacteria off the surface and rearranges their distribution. We find that the resulting pattern correlates with the spatial distribution of EPS: holes form where there is less EPS, whereas regions with more EPS act as strongholds against the scraping liquid front. These results show that heterogeneity in the microscale EPS skeleton of biofilms has profound consequences for later dynamics, including disruption. Because few attached cells suffice to regrow a biofilm, these results point to the importance of considering microscale heterogeneity when designing and assessing the effectiveness of biofilm removal strategies by mechanical forces. Biofilm disruption: patterns of weak spots Using air bubbles to disrupt biofilms reveals patterns in biofilm structure and susceptibility to damage that depend on a biofilm's age. Roman Stocker and colleagues at the Swiss Federal Institute of Technology in Zurich (ETH) used controlled flow of an air bubble to understand mechanical disruption of biofilms of Pseudomonas aeruginosa. This physical assault caused a characteristic pattern of holes in early-stage biofilms, different from the damage pattern in older biofilms. The holes were most likely to occur in regions that were relatively deficient in the polymers released by bacterial cells to form the extracellular structure of the biofilm. These findings highlight the importance of heterogeneities in the structure of biofilms as they form. The researchers suggest more attention should be given to age-related variations in microscale structure when designing strategies to disrupt biofilms.
- Publication
NPJ Biofilms & Microbiomes, 2017, Vol 3, Issue 1, pN.PAG
- ISSN
2055-5008
- Publication type
Article
- DOI
10.1038/s41522-017-0014-5