General method, using Mu-Mud1 dilysogens, to determine the direction of transcription of and generate deletions in the glnA region of Escherichia coli.

A general, genetic technique for determining the direction of transcription for bacterial genes is presented. By comparing the phenotype of Mu-Mud1 dilysogens with the phenotype of deletion-containing derivatives, the direction of transcription for the gene containing Mud1 can be unambiguously determined. This method can generate a series of strains containing deletions with predetermined endpoints, and strains with duplications of the region containing the Mud1 insertion. In Escherichia coli, the glnA and glnG genes are transcribed in the same direction.