Fig 3.

Determination of the transcription start sites of genDFM, genR, and genKH operons. ³²P-labeled pegenDFM01, pegenR01, and pegenKH04 primers for the genDFM operon, genR operon, and genKH operon were used to identify the transcription start sites of the three operons using primer extension analysis and high-resolution S1 mapping of wild-type RNA. Amounts of 20 to 50 μg of total RNA were obtained from strain RES167 grown in 3-HBA. Lanes P in A, B, and C show the product of primer extension. Lane S1 in C shows the product of high-resolution S1 mapping. The nucleotide sequence around the TSS (+1) is indicated by brackets, and the 5′ ends are enlarged and in boldface. (D and E) The location of the sequences upstream of the genDFM operon and the genR-genKH promoter regions are shown in detail. The first codon of each gene is given in italics. The TSSs are shown by +1 and arrows. The putative −10 and −35 promoter sequences are underlined, the regulator GenR primary binding sites are highlighted in gray, and their palindromic sequences are in boldface.