Enzymatic properties of endo-β-N-acetylglucosaminidases from developing tomato fruits and soybean seeds:: substrate specificity of plant origin endoglycosidase
Enzymatic properties of endo-β-N-acetylglucosaminidases from developing tomato fruits and soybean seeds:: substrate specificity of plant origin endoglycosidase
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DOI：
10.1016/s0304-4165(97)00155-4
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发表时间：
1998-06-05
影响因子：
3
通讯作者：
Ishiguro, Y
中科院分区：
文献类型：
--
作者：
Kimura, Y;Tokuda, T;Ishiguro, Y
研究了从大豆种子（Glycine max，Endo-GM）和番茄果实（Lycopersicum esculentum，Endo-LE）中部分纯化的内切-β-N-乙酰氨基葡萄糖苷酶（endo-beta-GlcNAc-ase）的底物特异性和其他酶学性质。这两种内切糖基化酶的底物特异性进行了探索，并与来自一些天然存在的糖蛋白的各种吡啶胺化N-聚糖进行了比较。对于Endo-GM和Endo-LE，几个带有α 1-2甘露糖残基的高甘露糖型糖链，Man（9-6）GlcNAc（2）-PA（PA是吡啶基氨基）（80-100%相对水解）是最受欢迎的底物，其次是Man（5）GlcNAc（2）-PA（Endo-LE为32%，Endo-GM为43%），典型的混合型结构（GlcNAc（1）Man（5）GlcNAc（2）-PA; Endo-LE为34%，Endo-GM为37%），然后是N-聚糖的共同核心五糖（Man（3）GlcNAc（2）-PA; Endo-GM为9%，Endo-LE为16%）。与此相反，Endo-GM和Endo-LE都能水解植物细胞中普遍存在的含木糖的N-聚糖（Man（3）Xyl（1）GlcNAc（2）-PA，Man（3）Fuc（1）Xyl（1）GlcNAc（2）-PA）。凝胶过滤法测得这两种内切糖基化酶的分子量约为62 kDa，在弱酸性区域（pH6.0 -6.5），Endo-GM和Endo-LE对Man（6）GlcNAc（2）-PA的活性最高。(C)1998 Elsevier Science B. V.保留所有权利。
Substrate specificity and some other enzymatic properties of partial purified endo-beta-N-acetylglucosaminidases (endo-beta-GlcNAc-ase) from developing soybean seeds (Glycine max, Endo-GM) and developing tomato fruits (Lycopersicum esculentum, Endo-LE) were studied. The substrate specificity of these two endoglycosidases was explored and compared with regard to various pyridylaminated N-glycans derived from some naturally occurring glycoproteins. For Endo-GM and Endo-LE, several high mannose-type sugar chains bearing alpha 1-2 mannosyl residue(s), Man(9-6)GlcNAc(2)-PA (PA is pyridylamino) (80-100% relative hydrolysis), were most favored substrates followed by Man(5)GlcNAc(2)-PA (32% for Endo-LE, 43% for Endo-GM), a typical hybrid-type structure (GlcNAc(1)Man(5)GlcNAc(2)-PA; 34% for Endo-LE, 37% for Endo-GM), and then the common core pentasaccharide of N-glycan (Man(3)GlcNAc(2)-PA; 9% for Endo-GM and 16% for Endo-LE). On the contrary, both Endo-GM and Endo-LE could bar:ly hydrolyze the xylose-containing N-glycans (Man(3)Xyl(1)GlcNAc(2)-PA, Man(3)Fuc(1)Xyl(1)GlcNAc(2)-PA) found ubiquitously in plant cells. The molecular mass of these two endoglycosidases was approximately 62 kDa by gel filtration and both Endo-GM and Endo-LE showed maximal activities for Man(6)GlcNAc(2)-PA in a weak acidic region (pH 6.0-6.5). (C) 1998 Elsevier Science B.V. All rights reserved.