Related Experiment Video
Updated: Aug 15, 2026

Single-cell Analysis of Bacillus subtilis Biofilms Using Fluorescence Microscopy and Flow Cytometry
Published on: February 15, 2012
Expression of streptolysin O gene in Bacillus subtilis
Abstract:
Streptolysin O (SLO) is a hemolytic, extracellular protein produced by Streptococcus pyogenes. A hybrid gene consisting of the promoter and signal sequence fused to the region encoding the mature sequence of the slo gene was constructed to secrete SLO in Bacillus subtilis. To increase secretion of SLO into the culture supernatant, several SLO expression vectors containing various combinations of promoters and pre-pro sequences were constructed. B. subtilis harboring pPA consisting of the P-43 promoter and the coding sequence of the pre region of the alkaline protease gene that was fused to the pro-mature region of the slo gene secreted SLO into media. The degree of hemolytic activity was found to be about 40-fold higher in the geneticaly engineered B. subtilis strain than that of S. pyogenes. Recombinant SLO was reacted with patients' sera infected by group A streptococci.
Related Concept Videos
Operons
Prokaryotic Transcriptional Activators and Repressors
Transcription of prokaryotic...
Coordination of Gene Expression Processes in Bacteria
Gram-negative Bacterial Protein Secretion Systems
Gene Regulation During Sporulation
Stringent Response in E. coli

