title: Microbial biofilm as a smart material.
abstract: 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.
authors: Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Kemitorvet 208, DK-2800 Kongens Lyngby, Denmark. garde@cbs.dtu.dk.
authors: Christian
authors: C
authors: Garde
authors: Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site, Cambridge CB2 1QW, UK. mw240@cam.ac.uk.
authors: Martin
authors: M
authors: Welch
authors: Biotech Research & Innovation Centre, Faculty of Health and Medical Sciences, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark. ferkinghoff-borg@lindinglab.org.
authors: Jesper
authors: J
authors: Ferkinghoff-Borg
authors: Biomedical Engineering, Department of Electrical Engineering, Technical University of Denmark, Ørsteds Plads 349, DK-2800 Kongens Lyngby, Denmark. tsams@dtu.dk.
authors: Thomas
authors: T
authors: Sams
mesh_terms: D018441:Biofilms; D015374:Biosensing Techniques; D053038:Quorum Sensing