Pullulan

Pullulan is a polysaccharide polymer consisting of maltotriose units, also known as α-1,4- ;α-1,6-glucan'. Three glucose units in maltotriose are connected by an α-1,4 glycosidic bond, whereas consecutive maltotriose units are connected to each other by an α-1,6 glycosidic bond. Pullulan is produced from starch by the fungus Aureobasidium pullulans. Pullulan is mainly used by the cell to resist desiccation and predation. The presence of this polysaccharide also facilitates diffusion of molecules both into and out of the cell.