Doctorante: Francesca Paragliola, Université de Naples, Italie

Résumé

Glycans are the most functionally and structurally diverse molecules, including critical roles in human and animal nutrition, plant cell wall remodelling, host-pathogen interactions, and thus having many industrial and pharmaceutical applications [1]. Through >3 billion years, Evolution shaped equal diversity of organisms and enzymes generating and degrading these molecules in an arms race. With technological advances, there is an acceleration in the discovery of novel carbohydrate-active enzymes (CAZymes) [2], which are then classified in the CAZy database [3]. In this context, the ODE project (Operon-based Discovery of carbohydrate-active Enzymes) aims to promote the discovery of new families of enzymes involved in glycan degradation. The key point is the analysis of the Polysaccharides Utilization Loci (PULs) in Bacteroidetes [3], genomic regions that aggregates all the components for the use of a given glycan. After bioinformatics analysis that identified several protein families of unknown function (PUF) in PULs, we focused on a list of 40 PUFs and selected diverse representatives to order 192 clones to be synthesized, produced and characterized in order to discover new families of CAZymes. During my time at AFMB, I analyzed 48 clones of this project, first via a high-throughput screening, second by low-throughput confirmation, and finally the positive ones were subject to preliminary characterizations.

[1]       Stevan A Springer and Pascal Gagneux, “Glycomics: Revealing the Dynamic Ecology and Evolution of Sugar Molecules,” Proteomics., vol. 176, no. 1, pp. 100–106, 2015, doi: 10.1177/0022146515594631.Marriage.

[2]       W. Helbert et al., “Discovery of novel carbohydrate-active enzymes through the rational exploration of the protein sequences space,” Proc. Natl. Acad. Sci. U. S. A., vol. 116, no. 13, pp. 6063–6068, 2019, doi: 10.1073/pnas.1815791116.

[3]       E. Drula, M.-L. Garron, S. Dogan, V. Lombard, B. Henrissat, and N. Terrapon, “The carbohydrate-active enzyme database: functions and literature,” Nucleic Acids Res., pp. 1–7, 2021, doi: 10.1093/nar/gkab1045.

[4]       N. Terrapon, V. Lombard, H. J. Gilbert, and B. Henrissat, “Automatic prediction of polysaccharide utilization loci in Bacteroidetes species,” Bioinformatics, vol. 31, no. 5, pp. 647–655, 2015, doi: 10.1093/bioinformatics/btu716.