Chem. J. Chinese Universities ›› 1998, Vol. 19 ›› Issue (6): 921.

• Articles • Previous Articles     Next Articles

Studies on the Thermostability and Conformation of Thermostable α-Amylase from Bacillus Licheniformis A.4041

ZHAO Ying, DONG Qing-Chu, MA He-Wen, YAN Bao-Shan, FEI Xiao-Fang, WANG Guo-Yan   

  1. Department of Molecular Biology, Jilin University, Changchun, 130023
  • Received:1997-07-11 Online:1998-06-24 Published:1998-06-24

Abstract: The influence of heat on the conformation and stability of α-amylase α-Ⅲ fraction from Bacillus Licheniformis A.4041 was studied by means of the fluorescence and CDspectra. Heated at 80 ℃ for 15 min, the enzyme hardly lost its activity. At the same time, a considerable change of its fluorescence and CDspectra was observed. It was shown that, comparing with the whole conformation of the enzyme molecule, the active site has a relative stability. Heated at 90 ℃ for 15 min, the conformational and active changes resulted by Ca 2+ and starch were different. The Ca2+ mainly affects the whole enzyme molecular conformations, whereas the substrate is important to sustain the activity. It indicates that the structure of enzymatic active site plays an important role to the thermostability of the α-Ⅲ.

Key words: Bacillus licheniformis, Thermostability, α-Amylase, Conformation

CLC Number: 

TrendMD: