I would like to add to what Davin C. Enigl wrote:
"There even seems to be communications between these cells because
when the inner cells are starving, the outer cells increase the flow
of nutrients to the inner cells. This is definitely a community if
not an organism".
More evidence for communication between biofilm cells is found
when discussing the phenomonon of "quorum sensing" in the bacterium,
_Vibrio fischeri_, associated with the light sensing organs of
marine animals such as the squid. The bacteria "sense" the density of
attached cells by secretion of an autoinducer, which reaches a
critical concentration necessary for the activation of the
luminescence genes when cell densities are high. The autoinducer
thus serves as an intercellular communication mechanism to determine
population density of the biofilm.
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| Denise Lindsay |
| Department of Microbiology |
| University of the Witwatersrand |
| Private Bag 3 |
| PO WITS 2050 |
| South Africa |
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