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From 2011.igem.org

Project Overview

The Grinnell College 2011 iGEM Team wishes to investigate the degradation of biofilms. A biofilm is a complex bacterial community structure that can exist on many different surfaces such as teeth, medical devices, and water pipes. Biofilms can contain harmful bacteria that are difficult to remove from surfaces because they are encased in a protective exopolymeric substance (EPS) matrix containing protein, polysaccharides, lipids, and nucleic acids. We explore two enzymes that have been shown to degrade biofilms or inhibit their formation. Esp is a serine protease from Staphylococcus epidermidis and DspB is a polysaccharide depolymerase from Aggregatibacter actinomycetemcomitans. Both target the EPS layer of biofilms that hold the communities together and attract other cells. DspB catalyzes the detachment of cells from the biofilm, while Esp is observed to have a similar effect on Staphylococcus aureus-induced biofilms. We will engineer the non-pathogenic aquatic bacterium Caulobacter crescentus to secrete these proteins by adding a Caulobacter-specific secretion tag to the end of the proteins along with a promoter and a ribosomal binding site. We will test whether Caulobacter can secrete these proteins and then compare how well these proteins reduce biofilm formation. In so doing, we will create a Caulobacter specific toolbox of BioBricks, facilitating future research with this versatile and useful bacterium.