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• 作者：Tingqiang Liu (1) (2)
  Hongshan Yu (2)
  Chunying Liu (2)
  Yuanhao Wang (2)
  Minqian Tang (3)
  Xiaodong Yuan (3)
  Ning Luo (2)
  Qingyu Wang (2)
  Xiaodong Xu (2)
  Fengxie Jin (2)
  
• 关键词：Biotransformation ; Steroidal saponin ; Protodioscin ; Aspergillus oryzae ; Protodioscin ; glycosidase ; 1 ; Cloning
• 刊名：Applied Microbiology and Biotechnology
• 出版年：2013
• 出版时间：December 2013
• 年：2013
• 卷：97
• 期：23
• 页码：10035-10043
• 全文大小：
• 作者单位：Tingqiang Liu (1) (2)
  Hongshan Yu (2)
  Chunying Liu (2)
  Yuanhao Wang (2)
  Minqian Tang (3)
  Xiaodong Yuan (3)
  Ning Luo (2)
  Qingyu Wang (2)
  Xiaodong Xu (2)
  Fengxie Jin (2)
  
  1. College of Science, Yanbian University, Yanji City, 133002, People Republic of China
  2. College of Biotechnology, Dalian Polytechnic University, Dalian, 116034, People Republic of China
  3. TaKaRa Biotechnology (Dalian) Co, Ltd, Dalian, 116600, People Republic of China
  
• ISSN：1432-0614

文摘

A novel protodioscin-(steroidal saponin)-glycoside hydrolase, named protodioscin-glycosidase-1 (PGase-1), was purified and characterized from the Aspergillus oryzae strain. The molecular mass of this enzyme was determined to be about 55kDa based on SDS-polyacrylamide gel electrophoresis. PGase-1 was able to hydrolyze the terminal 26-O-d-glucopyranoside of protodioscin (furostanoside) to produce dioscin (spirostanoside), and then further hydrolyze the terminal 3-O-(14)-l-rhamnopyranoside of dioscin to form progenin III. However, PGase-1 could hardly hydrolyze the 3-O-(12)-l-rhamnopyranoside of progenin III, 3-O-d-glucoside of trillin, and the 1-O-glycosides of ophiopogonin D (steroidal saponin). In addition, PGase-1 also could hydrolyze the d-galactopyranoside, d-glucopyranoside, and d-galactopyranoside of p-nitrophenyl-glycosides, but the enzyme could not hydrolyze the d-mannopyranoside, l-arabinopyranoside, d-glucopyranoside, d-xylopyranoside, and l-rhamnopyranoside of p-nitrophenyl-glycosides. These new properties of PGase-1 were significantly different from those of previously described steroidal saponin-glycosidases and the glycosidases currently described in Enzyme Nomenclature by the NC-IUBMB. The gene (termed as pgase-1) encoding PGase-1 was cloned, sequenced, and expressed in Pichia pastoris GS115. The complete nucleotide sequence of pgase-1 consists of 1,725bp. The recombinant PGase-1 from recombinant P. pastoris GS115 strain also showed the activity hydrolyzing glycosides of steroidal saponins which was similar to that of the wild-type PGase-1 from A. oryzae. The PGase-1 gene is highly similar to Aspergilli amylase (EC 3.2.1.1), and PGase-1 should be classified as glycoside hydrolase family 13 by the method of gene sequence-based classification. But the enzyme properties of PGase-1 are different from those of amylase in this family.