Other References:
Ruppen ME, Van Alstine GL, Band L. Control of intracellular serine protease expression in Bacillus subtilis. Journal of Bacteriology. 1988 Jan;170(1):136–140. DOI: 10.1128/jb.170.1.136-140.1988 PMID: 3121583, PMCID: PMC210617