一种新型真菌内切-β-N-乙酰氨基葡萄糖苷酶，其特异性作用于植物糖蛋白。

A novel fungal endo-beta-N-acetylglucosaminidase that specifically acts on plant glycoproteins.

作者信息

Sakamoto Y, Kurimura Y, Tsuji Y

机构信息

Research Laboratory of Higashimaru Shoyu Co. Ltd., Hyogo, Japan.

出版信息

Biosci Biotechnol Biochem. 1998 Jul;62(7):1344-50. doi: 10.1271/bbb.62.1344.

DOI:10.1271/bbb.62.1344

PMID:9720217

Abstract

An endo-beta-N-acetylglucosaminidase specific for plant glycoprotein oligosaccharides was purified from the culture fluid of a fungus. The Mr of the purified enzyme was 89,000. This enzyme was stable at pH 5.5-7.0, up to 30 degrees C, and showed the highest activity at pH 6.0. Among sugar chains tested, xylose-containing sugar chains (M3X, M3FX, and M2FX) were the most favored substrates. Oligomannose type (M3, M5, and M9) and hybrid type (GNM3) sugar chains were hydrolyzed much more slowly than xylose-containing sugar chains, and a complex type sugar chain (GN2M3) was not hydrolyzed at all by the enzyme. Moreover, the enzyme released sugar chains from native horseradish peroxidase and stem bromelain, which were not hydrolyzed by other endo-beta-N-acetylglucosaminidases (Endo H, D, and F). The enzyme could transfer the xylose-containing sugar chain from bromelain to DNS-Asn-GlcNAc-Fuc.

摘要

从一种真菌的培养液中纯化出一种对植物糖蛋白寡糖具有特异性的内切-β-N-乙酰氨基葡萄糖苷酶。纯化后的酶的相对分子质量为89,000。该酶在pH 5.5 - 7.0、温度高达30℃时稳定，在pH 6.0时表现出最高活性。在所测试的糖链中，含木糖的糖链（M3X、M3FX和M2FX）是最适宜的底物。寡甘露糖型（M3、M5和M9）和杂合型（GNM3）糖链的水解速度比含木糖的糖链慢得多，而复合型糖链（GN2M3）根本不被该酶水解。此外，该酶能从天然辣根过氧化物酶和菠萝蛋白酶中释放糖链，而其他内切-β-N-乙酰氨基葡萄糖苷酶（内切酶H、D和F）不能水解这些糖链。该酶能将菠萝蛋白酶中含木糖的糖链转移到DNS-Asn-GlcNAc-Fuc上。