FIG. 1.

Mapping of the transcriptional start of the bmy operon by primer extension analysis. (A) Primer extension was performed using the 5′-³²P-end-labeled primer rev1. The first four lanes result from dideoxynucleotide sequencing reactions. Arrows indicate the positions of the two adjacent bmyD transcriptional starts. The respective DNA sequences are shown on the right. The transcriptional starts are indicated by larger letters, whereas the putative −10 element is underlined. (B) The bmyD promoter region. The positions of the two adjacent transcriptional starts (boldface, +1), the translational start (boldface, Met), the putative ribosome binding site (underlined), the −35 and −10 hexamers (boxes), and the extended −10 region (double underlined) are indicated. The 5′ end sites of the oligonucleotides used for primer extension (rev1) and for construction of reporter fusions (bmyD1 to -D5) are marked by arrows. The two DegU binding sites (sites I and II) are shaded.