Gene Regulation by Attached Cells
Evidence is mounting that up- and down-regulation of a number of genes occurs in the attaching cells upon initial interaction with the substratum. Davies and Geesey demonstrated algC up-regulation in individual bacterial cells within minutes of attachment to surfaces in a flow cell system. This phenomenon is not limited to P. aeruginosa. Prigent-Combaret et al. found that 22% of these genes were up-regulated in the biofilm state, and 16% were down-regulated. Becker et al. showed that biofilms of Staphylococcus aureus were up-regulated for genes encoding enzymes involved in glycolysis or fermentation (phosphoglycerate mutase, triosephosphate isomerase, and alcohol dehydrogenase) and surmised that the up-regulation of these genes could be due to oxygen limitation in the developed biofilm, favoring fermentation. A recent study by Pulcini also showed that algD, algU, rpoS, and genes controlling polyphosphokinase (PPK) synthesis were up-regulated in biofilm formation of P. aeruginosa. Prigent-Combaret et al. opined that the expression of genes in biofilms is evidently modulated by the dynamic physicochemical factors external to the cell and may involve complex regulatory pathways.
Emerging Infectious Diseases. 2002;8(9) © 2002 Centers for Disease Control and Prevention (CDC)
Cite this: Biofilms: Microbial Life on Surfaces - Medscape - Sep 01, 2002.