CHLORAMPHENICOL ACETYLTRANSFERASE, A CYTOPLASMIC PROTEIN IS INCOMPATIBLE FOR EXPORT FROM BACILLUS-SUBTILIS

Bacillus subtilis cells expressing a hybrid protein (Lvs(ss)-Cat) cons isting of the B. amyloliquefaciens levansucrase signal peptide fused t o B. pumilus chloramphenicol acetyltransferase (Cat) are unable to exp ort Cat protein into the growth medium. A series of tripartite protein fusions was constructed by inserting various lengths of the Cat seque nces between the levansucrase signal peptide and staphylococcal protei n A or Escherichia coli alkaline phosphatase. Biochemical characteriza tion of the various Cat protein fusions revealed that multiple regions in the Cat protein were causing the export defect.