Restriction digests of the clone give the following sizes (kb): EcoRI/SmaI--7.0, 2.3; BamHI/EcoRI--6.55, 2.8; AccI--7.6, 1.8. The omega interposon terminates transcription in both directions. Transcriptional fusions constructed with this vector can be moved to the bacterial chromosome by using the transducing phage lambdaRZ5. This reduces problems inherent with multicopy plasmid systems like gene-dosage and titration effects. Promoter probe vector based on transcriptional fusion to lacZ. Constant efficiency of translation of lacZ is engineere d by incorporation of galK translational start signals.  |