Acidobacterium capsulatum由来の酸性α-グルコシダーゼの精製と諸性質 Purification and Properties of an Acid α-Glucosidase from Acidobacterium capsulatum

Access this Article

Search this Article

Author(s)

    • 杉尾 剛 SUGIO Tsuyoshi
    • 岡山大学農学部 Division of Biological Function and Genetic Resources Science, Faculty of Agriculture, Okayama University
    • 田中 英彦 TANAKA Hidehiko
    • 岡山大学農学部 Division of Biological Function and Genetic Resources Science, Faculty of Agriculture, Okayama University
    • 田野 達男 TANO Tatsuo
    • 岡山大学農学部 Division of Biological Function and Genetic Resources Science, Faculty of Agriculture, Okayama University

Abstract

中温好酸性従属栄養細菌Acidobacterium capsulatumから酸性α-グルコシダーゼを精製した.菌体をリゾチームーEDTAで処理し,上清をCM-SeparoseおよびMono-Sイオン交換クロマトグラフィーとSephacryl S-300を用いたゲル濾過により電気泳動的に単一に精製した.精製酵素は分子量65,000の単量体で,等電点は7.0であった.最適pHは3.0,最適温度は30℃,pH 3.5-7.0の間と10-50℃ で安定であった.pH 7.5以上と60℃ 以上では失活した.本酵素はアリルα -グリコシドやα-1,3 (nigerose),α 一1,4(maltose),α -1,6(isomaltose),α -1,β -2(sucrose)結合をもつオリゴ糖,可溶性澱粉を基質として,α 型のグルコースを遊離したことから,広い基質特異性をもつα -グルコシダーゼであると同定した.アミノ末端18残基のアミノ酸配列はSer-Ala-Thr-Gly-Ala-Pro-Trp-Trp-Lys-Asn-Ala-Val-lle-Tyr-Glu-Val-Tyr-Proであった.

Acidobacterium capsulatum, an acidophilic, mesophilic and chemoorganotrophic bacterium, constitutively produced the acid α-glucosidase. The enzyme, which was successively purified to homogeneity by CM-Sepharose, Sephacryl S-300 and Mono-S ion-exchange chromatography, was a monomeric protein, whose molecular weight was estimated to be 65, 000 by gel filtration and sodium dodecylsulfate-polyacrylamide gel electrophoresis. The enzyme exhibited optimum.activity at pH 4.5 and 30°C, being stable in the pH 3.5 to 7.0 region and in the range of 10 to 50°C. No activity was detected above pH 7.5 or above 60°C. Its isoelectric point was 7.0. The enzyme hydrolyzed pnitrophenyla-glycoside, oligosaccharides containing α-1, 3 (nigerose), α-1, 4 (maltose), α-1, 6 (isomaltose), and α-1, β-2 linkages (sucrose), and soluble starch and produced α-configurational glucose. These findings indicate that the A. capsulatum enzyme represents a novel type of α-glucosidase exhibiting a broad substrate specificity. Amino terminal analysis by a protein sequencer provided the sequence of the first eighteen residues as Ser-Ala-Thr-Gly-Ala-Pro-Trp-Trp-Lys-Asn-Ala-Val-Ile-Tyr-Glu-Val-Tyr-Pro.

Journal

  • Journal of Applied Glycoscience

    Journal of Applied Glycoscience 46(2), 121-127, 1999-06-30

    The Japanese Society of Applied Glycoscience

References:  25

Cited by:  1

Codes

  • NII Article ID (NAID)
    10008258802
  • NII NACSIS-CAT ID (NCID)
    AN10453916
  • Text Lang
    ENG
  • Article Type
    Journal Article
  • ISSN
    13403494
  • NDL Article ID
    4785693
  • NDL Source Classification
    ZP24(科学技術--化学・化学工業--糖・澱粉)
  • NDL Call No.
    Z17-15
  • Data Source
    CJP  CJPref  NDL  J-STAGE  JASI 
Page Top