Purification and substrate specificity of sweet corn .ALPHA.-glucosidase.

• MATSUI Hirokazu

  Department of Agricultural Chemistry, Faculty of Agriculture, Hokkaido University

• YAZAWA Itaru

  Department of Agricultural Chemistry, Faculty of Agriculture, Hokkaido University Present address: Kanebo Food Laboratory Ltd.

• CHIBA Seiya

  Department of Agricultural Chemistry, Faculty of Agriculture, Hokkaido University

抄録

An α-glucosidase was purified from sweet corn seeds by fractionation with ammonium sulfate, chromatographies on CM-Sepharose and Sepharose 4B, and gel filtrations on Sephadex G-100. The enzyme was homogeneous in disc electrophoretic analysis. The molecular weight was estimated to be about 9.6×10⁴ by SDS-disc electrophoresis.<br> The enzyme showed high activities toward maltose, nigerose, phenyl-α-maltoside, and maltooligosaccharides. The ratios of maximum velocity for maltose, nigerose, kojibiose, isomaltose, phenyl-α-glucoside, phenyl-α-maltoside, panose, turanose, and soluble starch were estimated to be 100: 78 : 17: 11 : 28 : 100 : 31 : 3.4 : 126, and the Km values for these substrates, 1.5 mM, 1.4 mM, 0.48 mM, 14 mM, 4.2 mM, 1.1 mM, 5.0 mM, 0.28 mM and 52 mg/ml, respectively. The maximum velocity for soluble starch was high, but this α-glucan was not a favorable substrate because the Km value was also very high. The V_max for maltooligosaccharides were somewhat dependent on the degree of polymerization (n). The Km values for substrates having four or more glucose units increased with the increase in n.

収録刊行物

• Agricultural and Biological Chemistry

  Agricultural and Biological Chemistry 45 (4), 887-894, 1981

  公益社団法人 日本農芸化学会

キーワード

• General Agricultural and Biological Sciences
• General Biochemistry, Genetics and Molecular Biology

詳細情報

• CRID: 1390282681439857664
• NII論文ID: 130000028542
• DOI: 10.1271/bbb1961.45.887
• COI: 1:CAS:528:DyaL3MXitVCgtLc%3D
• ISSN: 18811280
• ISSN: 00021369
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可