Abstract |
We present a mathematical model of mushroom-like architecture and cavity formation in Pseudomonas aeruginosa biofilms. We demonstrate that a proposed disparity in internal friction between the stalk and cap extracellular polymeric substances (EPS) leads to spatial variation in volumetric expansion sufficient to produce the mushroom morphology. The capability of diffusible signals to induce the formation of a fluid-filled cavity within the cap is then investigated. We assume that conversion of bacteria to the planktonic state within the cap occurs in response to the accumulation or depletion of some signal molecule. We (a) show that neither simple nutrient starvation nor signal production by one or more subpopulations of bacteria is sufficient to trigger localized cavity formation. We then (b) demonstrate various hypothetical scenarios that could result in localized cavity formation. Finally, we (c) model iron availability as a detachment signal and show simulation results demonstrating cavity formation by iron starvation. We conclude that iron availability is a plausible mechanism by which fluid-filled cavities form in the cap region of mushroom-like structures.
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Authors | James K Miller, Hope T Badawy, Curtis Clemons, K L Kreider, Pat Wilber, Amy Milsted, Gerald Young |
Journal | Journal of theoretical biology
(J Theor Biol)
Vol. 308
Pg. 68-78
(Sep 07 2012)
ISSN: 1095-8541 [Electronic] England |
PMID | 22677397
(Publication Type: Journal Article, Research Support, N.I.H., Extramural)
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Copyright | Copyright © 2012 Elsevier Ltd. All rights reserved. |
Chemical References |
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Topics |
- Biofilms
(drug effects, growth & development)
- Computer Simulation
- Iron Deficiencies
- Models, Biological
- Oligopeptides
(pharmacology)
- Pseudomonas aeruginosa
(drug effects, growth & development, physiology)
- Signal Transduction
(drug effects)
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