Demonstration of the enzymatic mechanisms of alpha-N-acetyl-D-glucosamine-1-phosphodiester N-acetylglucosaminidase (formerly called alpha-N-acetylglucosaminylphosphodiesterase) and lysosomal alpha-N-acetylglucosaminidase.
Demonstration of the enzymatic mechanisms of alpha-N-acetyl-D-glucosamine-1-phosphodiester N-acetylglucosaminidase (formerly called alpha-N-acetylglucosaminylphosphodiesterase) and lysosomal alpha-N-acetylglucosaminidase.
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演示 α-N-乙酰基-D-葡萄糖胺-1-磷酸二酯 N-乙酰氨基葡萄糖苷酶（以前称为 α-N-乙酰氨基葡萄糖磷酸二酯酶）和溶酶体 α-N-乙酰氨基葡萄糖苷酶的酶促机制。
DOI：
10.1016/0003-9861(83)90511-8
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发表时间：
1983
影响因子：
3.9
通讯作者：
Kornfeld,S
中科院分区：
文献类型：
--
作者：
Varki,A;Sherman,W;Kornfeld,S
已经描述了一种能够从新合成的溶酶体酶的高甘露糖型寡糖上存在的磷酸二酯中除去外部N-乙酰葡糖胺残基的酶。根据其底物特异性和抑制剂研究，该酶被称为α-N乙酰葡糖胺磷酸二酯酶。在这项研究中，它是由18 O富集法证明，该酶裂解的C O键，而不是O P键，因此，通过糖苷酶类型的机制。此外，该酶对α-N-乙酰葡糖胺1-磷酸无显著活性，因此需要潜在的磷酸二酯才能发挥活性。根据IUB对酶命名的建议，建议将该酶重新命名为α-N-乙酰-d-葡萄糖胺-1-磷酸二酯N-乙酰氨基葡萄糖苷酶（系统名称：2-乙酰氨基-2-脱氧-α-d-葡萄糖1-磷酸二酯乙酰氨基脱氧葡萄糖水解酶）。为方便起见，建议将其俗名为磷酸二酯糖苷酶。溶酶体α-N-乙酰葡糖胺糖苷酶也具有糖苷酶型机制，但对α-N-乙酰葡糖胺1-磷酸以及具有外部N-乙酰葡糖胺残基的磷酸二酯具有活性。
An enzyme that is capable of removing the outerN-acetylglucosamine residues from phosphodiesters present on the high-mannose-type oligosaccharides of newly synthesized lysosomal enzymes has been described. This enzyme has been called an α-Nacetylglucosaminylphosphodiesterase, based upon its substrate specificity and on inhibitor studies. In this study it is demonstrated by the18O enrichment method that the enzyme cleaves the CO bond rather than the OP bond, and therefore acts by a glycosidase type of mechanism. In addition, the enzyme has no significant activity toward α-N-acetylglucosamine 1-phosphate, and therefore requires an underlying phosphodiester for activity. In accordance with the IUB recommendations for enzyme nomenclature, it is therefore suggested that the enzyme be renamed α-N-acetyl-dglucosamine-1-phosphodiesterN-acetylglucosaminidase (systematic name, 2-acetamido-2-deoxy-α-d-glucose 1-phosphodiester acetamidodeoxyglucohydrolase). For convenience, the trivial name phosphodiester glycosidase is proposed. Lysosomal α-Nacetylglucosaminidase also has a glycosidase type of mechanism but it is active toward α-N-acetylglucosamine 1-phosphate as well as phosphodiesters with outerN-acetylglucosamine residues.