Abstract: The present disclosure relates to novel sialidase enzymes having a preference for cleaving N-glycolylneuraminic acid (Neu5Gc) from glycoconjugates over cleaving N-acetylneuraminic acid (Neu5Ac). The present disclosure further provides the polypeptide of such novel sialidase and its catalytic pockets; the recombinant host cells expressing the same, as well as the enzymatic, pharmaceutical, and consumable compositions comprising such novel sialidases. Probiotic compositions comprising a bacterium that expresses the sialidase having a preference for Neu5Gc over Neu5Ac, and methods for removing Neu5Gc from consumable products are also provided. Also disclosed are methods for treating or preventing various diseases, disorders, and inflammatory conditions in a subject using the novel sialidases.