– Exo-alpha-sialidase that catalyzes the hydrolytic cleavage of the terminal sialic acid (N-acetylneuraminic acid, Neu5Ac) of a glycan moiety in the catabolism of glycolipids, glycoproteins and oligosacharides. Displays high catalytic efficiency for gangliosides including alpha-(2->3)-sialylated GD1a and GM3 and alpha-(2->8)-sialylated GD3. Plays a role in the regulation of transmembrane signaling through the modulation of ganglioside content of the lipid bilayer and by direct interaction with signaling receptors, such as EGFR. Desialylates EGFR and activates downstream signaling in proliferating cells. Contributes to clathrin-mediated endocytosis by regulating sorting of endocytosed receptors to early and recycling endosomes.