Previously we reported [Deane, S. M., Maharaj, R., Robb, F. T. & Woods, D. R. (1987) Journal of General
Microbiology 133,2295-23021 that the production of a Vibrio dginoiyticus SDS-resistant alkaline serine protease
(Pro A) cloned in Escherichia coii was characterized by a 12 h delay between the synthesis of an inactive precursor
and secretion of active Pro A. Replacement of the V. dginoiyticus promoter region by the a-amylase promoter
region from Bacillus amyloliquefaciens resulted in the simultaneous synthesis and secretion of Pro A in E. coZi. The
V. dginoiyticusproA gene cloned on a shuttle vector did not produce active Pro A in Bacillus subtiiis. Although
Pro A has a typical Gram-positive signal sequence, it was not functional in B. subtiZis. Replacement of the Pro A
signal sequence with the a-amylase signal sequence resulted in the production of active Pro A in B. subtiiis.