Question

Microbiology question

Q:why Quorum sensing is important to biofilm dispersion?

Answer 1

quorum sensing in bacteria is an important aspect of social living. It helps one bacteria to communicate with other and so one population to the other. The communication between them is carried by releasing, sensing and responding to chemical signals. It is important for bacteria to understand various factors affecting its growth and colonisation i.e., external conditions, food availability, other competitors or harmful bacteria in surroundings etc.

Biofilms are complex communities in which different microbes live together in close proximity enveloped under external secretions of the whole community. In a biofilm, all microbes synchronised in such a way that they have more complex functions than the individual populations. Each bacteria respond to its external environment in a unique way but all signals together produce complex outcomes like the biofilm spreading. The quorum sensing between the different bacterial populations growing on solid material makes them switch to a biofilm formation. The interactions with other bacteria in a biofilm makes them produce cooperative actions like an expression of different adhesins, their cognate receptors, and exopolymeric components which help them to expand the biofilm. So depends upon the favourable conditions in the external environment they decide whether to continue the expansion of the biofilm or to revert it back. If any toxic chemical is spread in the surroundings sensed by a bacteria it produces signals to others and the quorum sensing makes all bacteria in the biofilm to stop spreading the biofilm in that direction.