Purification and characterization of the hyper-glycosylated extracellular α-glucosidase from Schizosaccharomyces pombe
Purification and characterization of the hyper-glycosylated extracellular α-glucosidase from Schizosaccharomyces pombe
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DOI：
10.1016/j.enzmictec.2004.06.018
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发表时间：
2005-10-03
影响因子：
3.4
通讯作者：
Chiba, S
中科院分区：
文献类型：
--
作者：
Okuyama, M;Tanimoto, Y;Chiba, S
从粟酒裂殖酵母细胞分泌的α-葡萄糖苷酶已作为均一蛋白从培养上清液中纯化。α-葡萄糖苷酶为高糖基化形式，其包含88%的糖组分，并且相对分子质量以1120 kDa计算。酶解去糖基化降低了α-葡萄糖苷酶的热稳定性和蛋白水解敏感性。通过MALDI-TOF NIS分析，推测该酶的27个潜在N-糖基化位点中的7个Asn残基（Asn 185、Asn 221、Asn 496、Asn 499、Asn 572、Asn 777和Asn 787;从成熟形式的N-末端开始编号）被修饰。S.粟酒裂殖酵母α-葡糖苷酶在催化位点中具有三个亚位点，因此在短底物如麦芽糖和麦芽三糖中比在长底物中更优选α-1，4-葡糖苷键。该酶还作用于α-1，2、α-1，3和α-1，6-糖苷键。(c)2005年爱思唯尔公司All rights reserved.
alpha-Glucosidase secreted from Schizosaccharomyces pombe cell has been purified as a homogeneous protein from culture supernatant. The alpha-glucosidase is hyper-glycosylated form, which included 88% of sugar components, and the relative molecular mass is calculated in 1120 kDa. Heat stability and proteolysis susceptibility of the alpha-glucosidase is descended by enzymatical deglycosylation. By MALDI-TOF NIS analysis, seven Asn residues (Asn185, Asn221, Asn496, Asn499, Asn572, Asn777 and Asn787; numbering from N-terminal of matured form) out of 27 potential N-glycosylation sites of the enzyme are presumed to be modified. The native form of S. pombe a-glucosidase have three subsites in the catalytic site and so prefer alpha-1,4-glucosidic linkage in short substrates, such as maltose and maltotriose, to longer substrate. The enzyme also acts on alpha- 1,2, alpha- 1,3, and alpha-1,6-glucosidic linkage. (c) 2005 Elsevier Inc. All rights reserved.