文献类型： 外文期刊

作者： Jang, Jin Myong ¹ ; Yang, Yi ¹ ; Wang, Ruonan ¹ ; Bao, Huifang ³ ; Yuan, Hongli ¹ ; Yang, Jinshui ¹ ;

作者机构： 1.China Agr Univ, Coll Biol Sci, State Key Lab Agrobiotechnol, Beijing 100193, Peoples R China

2.Kim II Sung Univ, Sch Lifesci, Pyongyang, North Korea

3.Xinjiang Acad Agr Sci, Inst Microbiol, Urumqi 830091, Xinjiang, Peoples R China

关键词： alpha-Galactosidase; Irpex lacteus; Raffinose family oligosaccharides; Soymilk; Pichia pastoris

期刊名称：INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES （ 影响因子：6.953； 五年影响因子：6.737 ）

ISSN： 0141-8130

年卷期： 2019 年 131 卷

页码：

收录情况： SCI

摘要： Raffinose family oligosaccharides (RFOs) negatively affect nutritional value of legume-derived food and feed. It has been challenging to develop a high performance alpha-galactosidase excelled on catalytic efficiency, thermostability, pH stability and protease-resistance that could efficiently hydrolyze RFOs. In this study, the first GH family 27 alpha-galactosidase gene from Irpex lacteus was cloned. The gene had an open reading frame of 1314 bp interrupted by 12 introns. The recombinant alpha-galactosidase expressed in Pichia pastoris (rILgalA) had an apparent molecular mass of 64 kDa and was highly N-glycosylated. rILgalA was maximally active at pH 4.8 and 70 degrees C. It was stable over a broad pH range of 3-11, retained 90% of its activity after incubation at 60 degrees C for 10 h and exhibited strong resistance to digestive proteases. Unlike many other alpha-galactosidases, rILgalA was hyperactive on RFOs. Its specific activities toward melibiose, raffinose and stachyose were 644, 755 and 833 U mg(-1), respectively. The corresponding K-cat/K-m values were 120, 130 and 180 mM(-1) s(-1), which were the highest among reported alpha-galactosidases. rILgalA almost completely hydrolyzed raffinose and stachyose in soymilk at 60 degrees C in 30 min. These superior properties would make rILgalA an ideal remover of RFOs in food and feed industries. (C) 2019 Elsevier B.V. All rights reserved.