Valérie BARBE

Molecular biologist by training and after having directed the Molecular biology laboratory for the study of genomes (laboratory of 14 people), responsible for collaborative projects subject to calls for tenders and after having spent more than 20 years working on genomes, especially bacteria (sequencing, assembly, annotation), I wanted to focus on a problem that was close to my heart: the biodegradability of plastics at sea.

The Genoscope is interested in the Biodegradation of plastics both for its research in biodiversity genomics and for its applications in bioremediation. Analyzes of communities supported by plastics in the Mediterranean have already been started within the framework of the Tara program. The discovery of enzymatic functions capable of degrading recalcitrant pollutants, originating from biodiversity, is an important theme of our guidelines, in particular for the elimination of chlordecone. Given the importance of the problem of microplastics in the ocean and the actions expected in the short term on this subject, particularly in Europe, it appeared necessary for the Genoscope to be able to work in closer collaboration with the LOMIC.

Different strains of marine bacteria and fungi are already isolated at LOMIC in order to characterize the biodegradation capacity of different conventional plastics (PE, PP, PS, PET,…) and biodegradable (PHBV, PCL, PLA, OXO,…). The biodegradation pathways are just beginning to be known, but only for PE and PET and never with marine strains. The marine environment is today considered to be the final recipient of this pollution. A better understanding of the biodegradation pathways of plastics will allow significant progress for research. To do this, the DNAs and RNAs of the "plastivore" strains will be extracted when they express biodegradation characteristics (in comparison with control conditions). The analysis of their genomes and their transcriptomes will be carried out to identify the genes expressed and the biochemical pathways of biodegradation.

Sampling during TARA Microplastic 2019 expedition