NAGA is a lysosomal a-N-acetylgalactosaminidase that cleaves non-reducing a-N-acetylgalactosaminyl moieties from glycoconjugates. Mature NAGA has 394aa and is trafficked to the lysosome via the mannose-6-phosphate receptor-mediated pathway. The enzyme is a retaining exoglycosidase, where both the substrate and product of the enzymatic reaction have the same anomeric configuration. Deficiency in NAGA results in increased urinary excretion and tissue accumulation of glycopeptides and oligosaccharides containing terminal aNacetylgalactosaminyl moieties, manifesting as Schindler's disease, an autosomal recessive disease with neuroaxonal dystrophy and other neurological symptoms. The enzyme can be used to remove a-N-acetylgalactosaminyl residues present on red blood cells thus converting blood type A to blood type O.