Mutations in the lac P2 promoter.
We used site-directed mutagenesis to generate mutations in the -10 region of the lac P2 promoter. The mutations were crossed onto lambda bacteriophage carrying the lac regulatory elements and an intact lacZ gene, and the effects of the various mutations were determined in vivo and in vitro. Two of four mutations had effects on the start point of the P2-directed transcript and had very little effect on lac expression. Another mutation, which abolishes P2 promoter activity in vitro, also had very little effect on lac expression in vivo. We suggest that the P2 promoter plays little or no role in the activation of the P1 promoter by catabolite activator protein in complex with cyclic AMP.
D001665:Binding Sites; D004720:Endonucleases; D004926:Escherichia coli / Q000235:genetics; D005090:Exodeoxyribonucleases; D005786:Gene Expression Regulation; D007763:Lac Operon; D009154:Mutation; D011401:Promoter Regions, Genetic; D015719:Single-Strand Specific DNA and RNA Endonucleases; D013329:Structure-Activity Relationship; D014158:Transcription, Genetic
D004720:Endonucleases; D005090:Exodeoxyribonucleases; C020133:exodeoxyribonuclease III; D015719:Single-Strand Specific DNA and RNA Endonucleases