text: N-Acetylglucosamine-1-phosphodiester alpha-N-Acetylglucosaminidase (EC 3.1.4.45; << phosphodiester alpha-GlcNAcase >>) catalyzes the second step in the synthesis of the [[ mannose 6-phosphate ]] determinant required for efficient intracellular targeting of newly synthesized lysosomal hydrolases to the lysosome.