By exploring fungal interactions with bacteria and diatoms, this project aims to elucidate how fungi contribute to glycan stability and carbon sequestration in marine environments. Fungi are ubiquitous in the world’s oceans and participate in the carbon cycle from surface waters to sediments. A2 FUN will determine whether fungal interactions with bacteria and diatoms limit energy-demanding glycan utilization and enhance aggregation and sinking, and thus carbon sequestration. We will hereby include saprotrophic yeast and filamentous fungi as well as parasitic, zoosporic fungi using isolated model systems.