Purification and characterization of a thermostable alpha-amylase from Bacillus stearothermophilus.
A soil isolate of Bacillus stearothermophilus was found to synthesize thermostable alpha-amylase. The enzyme was purified to homogeneity by ammonium sulfate fractionation and IECC on DEAE-cellulose column. The purified enzyme was considered to be a monomeric protein with a molar mass of 64 kDa, as determined by SDS-PAGE. The enzyme showed a wide range of pH tolerance and maximum activity at pH 7.0. The temperature tolerance was up to 100 degrees C with more than 90% catalytic activity; the maximum activity was observed at 50 degrees C. Divalent metal ions exhibited inhibitory effect on the enzyme activity. However, proteinase inhibitor did not react positively.
Microbiology Laboratory, Department of Botany, School of Life Sciences, Visva-Bharati, Santiniketan 731 235, India.
K
K
Chakraborty
B K
BK
Bhattacharyya
S K
SK
Sen
D004591:Electrophoresis, Polyacrylamide Gel; D001411:Geobacillus stearothermophilus / Q000201:enzymology* / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D012988:Soil Microbiology; D013696:Temperature; D000516:alpha-Amylases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism
D000516:alpha-Amylases