We isolated a beta-N-acetylglucosaminidase encoding gene and its cDNA from the filamentous fungus Aspergillus nidulans, and designated it nagA. The nagA gene contained no intron and encoded a polypeptide of 603 amino acids with a putative 19-amino acid signal sequence. The deduced amino acid sequence was very similar to the sequence of Candida albicans Hex1 and Trichoderma harzianum Nag1. Yeast...

Adsorptive endocytosis of alpha-N-acetylglucosaminidase from human urine by isolated rat hepatocytes is inhibited by glycoproteins, polysaccharides and sugars that are known to bind to cell-surface receptors specific for either terminal galactose/N-acetylgalactosamine residues, terminal mannose residues or mannose 6-phosphate residues. Recognition of alpha-N-acetylglucosaminidase by a cell-surf...

Fertilization in the mouse is initiated by sperm beta 1,4-galactosyltransferase (GalTase) binding to terminal N-acetylglucosamine residues on the zona pellucida glycoprotein ZP3. Binding of ZP3 induces exocytosis of the sperm acrosome, whose contents are believed to digest a penetration slit in the zona matrix through which sperm reach the egg. As a consequence of acrosomal exocytosis, GalTase ...

Cultured non-parenchymal rat liver cells internalize human urine alpha-N-acetylglucosaminidase, human skin beta-N-acetylglucosaminidase and pig kidney alpha-mannosidase. Different heat-stabilities of endocytosed and endogenous alpha-mannosidase activity provided indirect evidence that the increase in intracellular activity resulted from uptake. The high efficiency and the saturation kinetics of...

A procedure for the isolation of exo-beta-N-acetylglucosaminidase mutants, by using a plate assay method incorporating a fluorescent substrate, has been developed. A mutant lacking exo-beta-N-acetylglucosaminidase activity has been isolated and shown to grow, divide, autolyze, and sporulate as well as the parental strain.

The mammalian egg must be fertilized by only one sperm to prevent polyploidy. In most mammals studied to date, the primary block to polyspermy occurs at the zona pellucida, the mammalian egg coat, after exocytosis of the contents of the cortical granules into the perivitelline space. The exudate acts on the zona, causing it to lose its ability to bind sperm and to be penetrated by sperm previou...

It has been demonstrated that solid hepatoma lysosomes lack hyaluronidase activity, whereas normal rat liver lyso somes contain a high level of this enzyme. This result was also found with lysosomes from an ascites hepatoma, Walker carcinoma 256, and virally transformed BHK cells. In contrast, 0-yV-acetylglucosaminidase activity was shown to be present in lysosomes from tumor cells, although it...

Endo-β-N-acetylglucosaminidase H (Endo H, EC3.2.1.96) is a glycohydrolase that is widely used in the study of glycoproteins. The present study aimed to assess the effect of high-level endo-β-N-acetylglucosaminidase H expression in Pichia pastoris. The DNA coding sequence of this enzyme was optimized based on the codon usage bias of Pichia pastoris and synthesized through overlapping PCR. This n...

Five of the six known glycosidases in the culture medium of Streptococcus pneumoniae have been purified from 600to 55,000-fold by a systematic procedure of ion exchange and affinity chromatography. Following partial separation of the glycosidases on DEAE-Sephadex, the neuraminidase, the endo-cu-N-acetylgalactosaminidase, the /3-galactosidase, and the P-iV-acetylglucosaminidase were further puri...