Eneyskaya E V, Kulminskaya A A, Kalkkinen N, Nifantiev N E, Arbatskii N P, Saenko A I, Chepurnaya O V, Arutyunyan A V, Shabalin K A, Neustroev K N
Molecular and Radiation Biophysics Division, Petersburg Nuclear Physics Institute, Russian Academy of Science, 188300 Gatchina, Orlova roscha, Russia.
Glycoconj J. 2001 Oct;18(10):827-34. doi: 10.1023/a:1021163720282.
An alpha-L-fucosidase (E.C. 3.2.1.51) exhibiting a wide aglycon specificity expressed in ability of cleaving alpha1 --> 6-, alpha1 -->3-, alpha1 --> 4-, and alpha1 --> 2-O-fucosyl bonds in fucosylated oligosaccharides, has been isolated from culture filtrate of Thermus sp. strain Y5. The alpha-L-fucosidase hydrolyzes p-nitrophenyl alpha-L-fucopyranoside with V(max) of 12.0 +/- 0.1 microM/min/mg and K(m) = 0.20 +/- 0.05 mM and is able to cleave off about 90% of total L-fucose from pronase-treated fractions of fucosyl-containing glycoproteins and about 30% from the native glycoproteins. The purified enzyme is a tetramer with a molecular mass of 240 +/- 10 kDa consisting of four identical subunits with a molecular mass of 61.0 +/- 0.5 kDa. The N-terminal sequence showed homology to some alpha-L-fucosidases from microbial and plant sources. Hydrolysis of p-nitrophenyl alpha-L-fucopyranoside occurs with retention of the anomeric configuration. Transglycosylating activity of the alpha-L-fucosidase was demonstrated in reactions with such acceptors as alcohols, N-acetylglucosamine and N-acetylgalactosamine while no transglycosylation products were observed in the reaction with p-nitrophenyl alpha-L-fucopyranoside. The enzyme can be classified in glycosyl hydrolase family 29.
从嗜热栖热菌属菌株Y5的培养滤液中分离出一种α-L-岩藻糖苷酶（E.C. 3.2.1.51），该酶表现出广泛的苷元特异性，能够裂解岩藻糖基化寡糖中的α1→6-、α1→3-、α1→4-和α1→2-O-岩藻糖基键。该α-L-岩藻糖苷酶水解对硝基苯基α-L-岩藻糖苷，V(max)为12.0±0.1微摩尔/分钟/毫克，K(m)=0.20±0.05毫摩尔，并且能够从经链霉蛋白酶处理的含岩藻糖基糖蛋白组分中裂解掉约90%的总L-岩藻糖，从天然糖蛋白中裂解掉约30%。纯化后的酶是一种四聚体，分子量为240±10千道尔顿，由四个分子量为61.0±0.5千道尔顿的相同亚基组成。N端序列显示与一些来自微生物和植物来源的α-L-岩藻糖苷酶具有同源性。对硝基苯基α-L-岩藻糖苷的水解反应发生时，异头构型得以保留。该α-L-岩藻糖苷酶的转糖基化活性在与醇、N-乙酰葡糖胺和N-乙酰半乳糖胺等受体的反应中得到证实，而在与对硝基苯基α-L-岩藻糖苷的反应中未观察到转糖基化产物。该酶可归类于糖基水解酶家族29。
