Insoluble but enzymatically active α-amylase from Bacillus licheniformis

Abstract

Abstract:The gene encoding thermostable α-amylase from Bacillus licheniformis consisting of 483 amino acid residues (mature protein) was cloned and expressed in Escherichia coli under the control of T7 promoter. The analysis of the soluble and insoluble fractions after lyzing the host cells revealed that recombinant α-amylase was produced in insoluble aggregates. Despite being produced in the insoluble aggregates the recombinant enzyme was highly active with a specific activity of 408 U/mg.

Characterization of moderately thermostable α-amylase-producing Bacillus licheniformis from decaying potatoes and sweet potatoes

“…The α-amylase in this study yielded a better activity at an alkaline pH of 8 compared with that reported by Ibrahim et al (2013), who obtained a maximum activity at a pH of 5. The α-amylase of this study had a higher alkaline performance (at a pH of 8.0) than that of Rashid et al (2009), who obtained a maximum activity at a pH of 6. The activity decreased at higher or lower pH values.…”

Effective solubilization and single-step purification of Bacillus licheniformis α-amylase from insoluble aggregates

“…Plasmid pET-21a (Novagen) was used for the expression of the gene. The expression vector containing the -amylase gene (pET-amy) (Rashid et al 2009) was used to transform E. coli strain BL21-CodonPlus(DE3)-RIL. Host cells carrying pET-amy plasmid were grown overnight at 37 °C in LB medium containing ampicillin (50 µg/mL).…”