By investigating glycan-binding proteins on the surface of bacteria, this project investigates why some glycans can escape this trap and contribute to carbon sequestration. Its hypothesis is that non-catalytic glycan-binding proteins, which are the first step in glycan utilization, represent a bottleneck in substrate acquisition and therefore limit degradation. B2 TRAP aims to provide detailed insight into ligand binding and its limitations. The identification of non-binding orphans in different groups of glycans, but also of abiotic conditions that affect binding, will contribute to a better understanding of carbon fluxes in the oceans.