The Involvement of Cell-to-Cell Signals in the Development of a Bacterial Biofilm

TLDR

Bacteria commonly form sessile biofilm communities that are morphologically and physiologically distinct from planktonic cells. A quorum‑sensing signal regulates Pseudomonas aeruginosa biofilm development; a lasI mutant produces flat, SDS‑sensitive biofilms that revert to normal when supplied with synthetic signal, indicating that targeting this intercellular signal could control biofilm growth on medical devices and in cystic fibrosis.

Abstract

Bacteria in nature often exist as sessile communities called biofilms. These communities develop structures that are morphologically and physiologically differentiated from free-living bacteria. A cell-to-cell signal is involved in the development of Pseudomonas aeruginosa biofilms. A specific signaling mutant, a lasI mutant, forms flat, undifferentiated biofilms that unlike wild-type biofilms are sensitive to the biocide sodium dodecyl sulfate. Mutant biofilms appeared normal when grown in the presence of a synthetic signal molecule. The involvement of an intercellular signal molecule in the development of P. aeruginosa biofilms suggests possible targets to control biofilm growth on catheters, in cystic fibrosis, and in other environments where P. aeruginosa biofilms are a persistent problem.