Article
Site-directed mutagenesis of a thermostable alpha-amylase from Bacillus stearothermophilus: putative role of three conserved residues.
Journal of biochemistry - 1 Feb 1990
Vihinen M, Ollikka P, Niskanen J, Meyer P, Suominen I, Karp M, Holm L, Knowles J, Mäntsälä P
Abstract excerpt
The relationship between structure, activity, and stability of the thermostable Bacillus stearothermophilus alpha-amylase was studied by site-directed mutagenesis of the three most conserved residues. Mutation of His-238 to Asp involved in Ca2+ and substrate binding reduced the specific activity and thermal stability, but did not affect the pH and temperature optima. Replacement of Asp-331 by Glu in the active...
Topics
- Amino Acid Sequence
- Amylases
- Arginine
- Aspartic Acid
- Bacterial Proteins
- Enzyme Stability
- Geobacillus stearothermophilus
- Histidine
- Hot Temperature
- Models, Molecular
- Molecular Sequence Data