ABSTRACT
In this chapter, the authors describe several applications of their galK fusion vector system to the study of prokaryotic promoters and terminators. They show how the system can be used to characterize promoter signals created by mutation, to select and functionally characterize mutations that inactivate promotion, and to isolate and characterize mutations in transcription termination signals. The authors examine the utility of the fusion vector system for quantitative assessment of regulatory signal function both in vivo and in vitro. The ability to select for or against galK expression suggests the potential of using the pKO vector system for isolating mutations in transcriptional regulatory elements. The pKO system can be used to obtain mutations in essentially any DNA sequence that functions as a prokaryotic promoter signal. The pKO system also can be used for the isolation and characterization of transcription termination signals.
