Next Article in Journal
Ionizing Radiation Detectors Based on Ge-Doped Optical Fibers Inserted in Resonant Cavities
Next Article in Special Issue
Performance and Stress Analysis of Metal Oxide Films for CMOS-Integrated Gas Sensors
Previous Article in Journal
Sol-Gel Deposition of Iridium Oxide for Biomedical Micro-Devices
Previous Article in Special Issue
Improving Atomic Force Microscopy Imaging by a Direct Inverse Asymmetric PI Hysteresis Model
Article Menu

Export Article

Open AccessReview
Sensors 2015, 15(2), 4229-4241;

Microbial Biofilm as a Smart Material

Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Kemitorvet 208, DK-2800 Kongens Lyngby, Denmark
Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site, Cambridge CB2 1QW, UK
Biotech Research & Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
Biomedical Engineering, Department of Electrical Engineering, Technical University of Denmark, Ørsteds Plads 349, DK-2800 Kongens Lyngby, Denmark
Authors to whom correspondence should be addressed.
Received: 16 January 2015 / Revised: 8 February 2015 / Accepted: 9 February 2015 / Published: 12 February 2015
(This article belongs to the Special Issue Smart Materials for Switchable Sensors)
Full-Text   |   PDF [340 KB, uploaded 12 February 2015]


Microbial biofilm colonies will in many cases form a smart material capable of responding to external threats dependent on their size and internal state. The microbial community accordingly switches between passive, protective, or attack modes of action. In order to decide which strategy to employ, it is essential for the biofilm community to be able to sense its own size. The sensor designed to perform this task is termed a quorum sensor, since it only permits collective behaviour once a sufficiently large assembly of microbes have been established. The generic quorum sensor construct involves two genes, one coding for the production of a diffusible signal molecule and one coding for a regulator protein dedicated to sensing the signal molecules. A positive feedback in the signal molecule production sets a well-defined condition for switching into the collective mode. The activation of the regulator involves a slow dimerization, which allows low-pass filtering of the activation of the collective mode. Here, we review and combine the model components that form the basic quorum sensor in a number of Gram-negative bacteria, e.g., Pseudomonas aeruginosa. View Full-Text
Keywords: quorum sensing; size sensor; AHL; PQS; Pseudomonas aeruginosa; OdDHL; signal molecule; filtering; switch; biofilm quorum sensing; size sensor; AHL; PQS; Pseudomonas aeruginosa; OdDHL; signal molecule; filtering; switch; biofilm
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Garde, C.; Welch, M.; Ferkinghoff-Borg, J.; Sams, T. Microbial Biofilm as a Smart Material. Sensors 2015, 15, 4229-4241.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top