Team:Lyon-INSA

Team project description

Biofilms are responsible for billions of dollars in production losses and treatment costs in the industry every year. Biofilm-related problems are major concerns in the food industry where they can cause food spoilage or poisoning, in health industry because of pathogens' persistence and dispersal, or in the oil and water industry where they induce corrosion. Assuming that the environment is already over-saturated with harmful chemical products such as biocides, with indubitable long term health effects there is a great need for novel solutions to reduce detrimental biofilm effects.

To reduce the use of biocides, the INSA-Lyon iGEM team aims to engineer bacterial “torpedo” capable to infiltrate and destroy biofilms formed on industrial equipments, pipes or reservoirs. Industrial surfaces will then be protected from further deleterious contamination by either a surfactant coating or the establishment of a protective biofilm.

Our experimental model consists of Staphylococcus epidermidis as the detrimental biofilm, and Bacillus subtilis as the “Biofilm Killer” agent. Three complementary modules will be constructed to arm our “Biofilm Killer” strain:

The first step will be to fit Bacillus subtilis swimmers with both a biocide and a biofilm-distructuring agent. Irrigation of these active substances in the biofilm should be facilitated by the tunneling activity of these cells.

In a second step, to prevent surface recolonisation by unwanted biofilms., we will engineer our "Biofilm Killer" strain with a conditional production of surfactin, a naturally toxic bio-surfactant produced by B. subtilis and displaying well-known antimicrobial properties.

Finally, we will engineer the Bacterial Killer to establsih a conditional of a competitive barrier flora, to futher prevent surface recolonisation in the long temr, by inhibiting the expression of abrB, its main biofilm formation repressor gene.

Bacillus strains are non-pathogenic, and do not cause equipment degradation by corrosion: their settlement on surfaces represents biocide-alternative strategy to prevent the formation of new dangerous biofilm. This project provides a potential economy and environmental friendly solution for the control of unwanted biofilm.