Compositions and methods are disclosed herein that relate to the development of fusion promoters for regulating gene expression in bacteria. Embodiments include fusion promoters comprising one or more operators linked to a promoter that is modified to have altered activity in Gram-positive organisms. Vectors and cells containing these fusion promoters are also described. Other embodiments include, methods of using these fusion promoters to regulate nucleic acid and/or polypeptide expression, methods of using these fusion promoters to identify proliferation-required genes, and methods of using these fusion promoters to identify molecules having potential antibiotic activity.
