The Lascaux cave, currently listed as World Heritage Site by UNESCO, was discovered in 1940 in France and opened after World War II. It houses 18,000 years old parietal (‘cave art’) paintings and covers a large period of prehistory. There was a large number of visitors but authorities had to close the access at the cave in 1963 because of algal contamination brought by visitors. Since then, several treatments have been applied in the cave: fungicides, antibiotics or even chemical products. After each new treatment, scientists observed new microorganisms appearing and growing. Currently, the only way to fight against contamination is the regular scratching of the walls. The microorganisms present at the moment are bacteria (Pseudomonas fluorescens and Ralstonia) and fungi (Fusarium solani and Ochroconis sp.), these last ones being responsible of black and white stains on the paintings.
An innovative solution using synthetic biology
Our project consists in a biological solution to restrain the damages to the cave. We wish to create a bacterium provided with a predation system that will kill bacteria already present in the cave and living in symbiosis with fungi. This bacterium will also have the capacity to product fungicides to fight against several infections. These two systems will be linked by a toxin/antitoxin system in order to kill the bacterium if she mutates and loses one of the function we implanted. To prevent the modified bacteria from spreading out of the cave, we will put a regulation system that will kill them when they detect too much light.
We will test our system by reproducing the cave conditions in laboratory: we will grow some Pseudomonas fluorescens and Fusarium solani on painted rocks at 10°C with a high humidity rate and we will apply our modified bacteria.
The team members are Fanny LECLERC, Camille ROUX, Anissa DIEUDONNE, Oumnia KARIM, Eve Coutant, Marine DUBOIS, Soukaïna TIMOUMA and Manon BARTHE. We are all from Toulouse in France, studying biochemistry engineering, bioinformatics, microbiology or agrosciences.
For more information, you can visit the team’s Facebook page https://www.facebook.com/IGEM-Toulouse-1604834019761538/ and follow them on Twitter @iGEM_ToulouseFR.