Efficient production of Bacillus stearothermophilus alpha-amylase in Bacillus brevis by altering its signal peptide.

To investigate the role of signal peptides in extracellular production in Bacillus brevis, the Bacillus stearothermophilus alpha-amylase signal peptide was systematically altered and the effects were analyzed in B. brevis. Efficient extracellular production of the amylase in B. brevis was accomplished either by introducing point mutations at positions between -6 and -4 or by replacing the whole signal peptide with that of B. brevis middle wall protein.