Characterization of Enzymatic Properties of Streptomyces albus Amylase Expressed in Recombinant Bacillus subtilis

재조합 Bacillus subtilis 에서 발현된 Streptomyces albus 유래 amylase 의 효소공학적 특성

  • Park, Geun-Woo (Department of Food Science and technology and Research Center for New Bio-materials in Agriculture, Seoul National University) ;
  • Kim, Myoung-Dong (Department of Food Science and technology and Research Center for New Bio-materials in Agriculture, Seoul National University) ;
  • Ahn, Jang-Woo (Department of Food Science and Technology, Chungkang College of Cultural Industries) ;
  • Kim, Young-Bae (Department of Food Science & Technology, Korea University) ;
  • Seo, Jin-Ho (Department of Food Science and technology and Research Center for New Bio-materials in Agriculture, Seoul National University)
  • 박근우 (서울대학교 식품공학과 및 농업생물신소재 연구센터) ;
  • 김명동 (서울대학교 식품공학과 및 농업생물신소재 연구센터) ;
  • 안장우 (청강문화산업전문대학 식품공업과) ;
  • 김영배 (고려대학교 식품공학과) ;
  • 서진호 (서울대학교 식품공학과 및 농업생물신소재 연구센터)
  • Published : 1998.12.01

Abstract

The research was undertaken to characterize enzymatic properties of Streptomyces albus amylase expressed in recombinant Bacillus subtilis. Molecular weight and pI of the purified enzyme were estimated to be 50 kD by SDS-PAGE and 4.3 by isoelectric focusing. The optimum temperature and optimum pH were $45^{\circ}C$ and 6.0, respectively. D-and Z-value were estimated to measure thermostability of the purified enzyme. The Z-value was estimated $17.7^{\circ}C$, which is lower than typical amylase. Maltotetraose was produced as a major component from soluble starch in the early state of reaction but gradually degraded to maltose. Thin layer chromatography was also performed to analyze the reaction products. The parameters involved in Michaelis-Menten enzyme kinetics were found to be the maximum velocity of 0.37 mM/min and the Michaelis constant of 0.13%, respectively.

Keywords

recombinant Bacillus subtilis;maltooligosaccharides;amylase;maltotetraose